diff --git a/app/build.gradle b/app/build.gradle
index 5977b347..62eb8e31 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -186,7 +186,7 @@ ext {
 }
 
 dependencies {
-    implementation "io.github.wulkanowy:sdk:1.7.0"
+    implementation "io.github.wulkanowy:sdk:09e5215894"
 
     coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:1.1.8'
 
diff --git a/app/src/main/java/io/github/wulkanowy/data/db/dao/MailboxDao.kt b/app/src/main/java/io/github/wulkanowy/data/db/dao/MailboxDao.kt
index 8589db31..c44ecd0c 100644
--- a/app/src/main/java/io/github/wulkanowy/data/db/dao/MailboxDao.kt
+++ b/app/src/main/java/io/github/wulkanowy/data/db/dao/MailboxDao.kt
@@ -11,7 +11,4 @@ interface MailboxDao : BaseDao<Mailbox> {
 
     @Query("SELECT * FROM Mailboxes WHERE userLoginId = :userLoginId ")
     suspend fun loadAll(userLoginId: Int): List<Mailbox>
-
-    @Query("SELECT * FROM Mailboxes WHERE userLoginId = :userLoginId AND studentName = :studentName ")
-    suspend fun load(userLoginId: Int, studentName: String): Mailbox?
 }
diff --git a/app/src/main/java/io/github/wulkanowy/data/repositories/MailboxRepository.kt b/app/src/main/java/io/github/wulkanowy/data/repositories/MailboxRepository.kt
index 7f597492..8c1097bd 100644
--- a/app/src/main/java/io/github/wulkanowy/data/repositories/MailboxRepository.kt
+++ b/app/src/main/java/io/github/wulkanowy/data/repositories/MailboxRepository.kt
@@ -32,17 +32,22 @@ class MailboxRepository @Inject constructor(
 
     suspend fun getMailbox(student: Student): Mailbox {
         val isExpired = refreshHelper.shouldBeRefreshed(getRefreshKey(cacheKey, student))
-        val mailbox = mailboxDao.load(student.userLoginId, student.studentName)
+        val mailboxes = mailboxDao.loadAll(student.userLoginId)
+        val mailbox = mailboxes.filterByStudent(student)
 
         return if (isExpired || mailbox == null) {
             refreshMailboxes(student)
-            val newMailbox = mailboxDao.load(student.userLoginId, student.studentName)
+            val newMailbox = mailboxDao.loadAll(student.userLoginId).filterByStudent(student)
 
             requireNotNull(newMailbox) {
-                "Mailbox for ${student.userName} - ${student.studentName} not found!"
+                "Mailbox for ${student.userName} - ${student.studentName} not found! Saved mailboxes: $mailboxes"
             }
 
             newMailbox
         } else mailbox
     }
+
+    private fun List<Mailbox>.filterByStudent(student: Student): Mailbox? = find {
+        it.studentName.trim() == student.studentName.trim()
+    }
 }
diff --git a/app/src/test/java/io/github/wulkanowy/data/repositories/MailboxRepositoryTest.kt b/app/src/test/java/io/github/wulkanowy/data/repositories/MailboxRepositoryTest.kt
new file mode 100644
index 00000000..56e31563
--- /dev/null
+++ b/app/src/test/java/io/github/wulkanowy/data/repositories/MailboxRepositoryTest.kt
@@ -0,0 +1,132 @@
+package io.github.wulkanowy.data.repositories
+
+import io.github.wulkanowy.data.db.dao.MailboxDao
+import io.github.wulkanowy.data.db.entities.Mailbox
+import io.github.wulkanowy.data.db.entities.MailboxType
+import io.github.wulkanowy.data.db.entities.Student
+import io.github.wulkanowy.sdk.Sdk
+import io.github.wulkanowy.utils.AutoRefreshHelper
+import io.mockk.MockKAnnotations
+import io.mockk.Runs
+import io.mockk.coEvery
+import io.mockk.impl.annotations.MockK
+import io.mockk.impl.annotations.SpyK
+import io.mockk.just
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.runTest
+import org.junit.Assert.assertEquals
+import org.junit.Before
+import org.junit.Test
+import java.time.Instant
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class MailboxRepositoryTest {
+
+    @SpyK
+    private var sdk = Sdk()
+
+    @MockK
+    private lateinit var mailboxDao: MailboxDao
+
+    @MockK
+    private lateinit var refreshHelper: AutoRefreshHelper
+
+    private lateinit var systemUnderTest: MailboxRepository
+
+    @Before
+    fun setUp() {
+        MockKAnnotations.init(this)
+
+        coEvery { refreshHelper.shouldBeRefreshed(any()) } returns false
+        coEvery { refreshHelper.updateLastRefreshTimestamp(any()) } just Runs
+        coEvery { mailboxDao.deleteAll(any()) } just Runs
+        coEvery { mailboxDao.insertAll(any()) } returns emptyList()
+        coEvery { mailboxDao.loadAll(any()) } returns emptyList()
+        coEvery { sdk.getMailboxes() } returns emptyList()
+
+        systemUnderTest = MailboxRepository(
+            mailboxDao = mailboxDao,
+            sdk = sdk,
+            refreshHelper = refreshHelper,
+        )
+    }
+
+    @Test(expected = IllegalArgumentException::class)
+    fun `get mailbox that doesn't exist`() = runTest {
+        val student = getStudentEntity(
+            userName = "Stanisław Kowalski",
+            studentName = "Jan Kowalski",
+        )
+        coEvery { sdk.getMailboxes() } returns emptyList()
+
+        systemUnderTest.getMailbox(student)
+    }
+
+    @Test
+    fun `get mailbox for user with additional spaces`() = runTest {
+        val student = getStudentEntity(
+            userName = "  Stanisław Kowalski  ",
+            studentName = "  Jan Kowalski  ",
+        )
+        val expectedMailbox = getMailboxEntity("Jan Kowalski ")
+        coEvery { mailboxDao.loadAll(any()) } returns listOf(
+            expectedMailbox,
+        )
+
+        val selectedMailbox = systemUnderTest.getMailbox(student)
+        assertEquals(expectedMailbox, selectedMailbox)
+    }
+
+    @Test(expected = IllegalArgumentException::class)
+    fun `get mailbox for student with strange name`() = runTest {
+        val student = getStudentEntity(
+            userName = "Stanisław Kowalski",
+            studentName = "J**** K*****",
+        )
+        val expectedMailbox = getMailboxEntity("Jan Kowalski")
+        coEvery { mailboxDao.loadAll(any()) } returns listOf(
+            expectedMailbox,
+        )
+
+        systemUnderTest.getMailbox(student)
+    }
+
+    private fun getMailboxEntity(
+        studentName: String,
+    ) = Mailbox(
+        globalKey = "",
+        fullName = "",
+        userName = "",
+        userLoginId = 123,
+        studentName = studentName,
+        schoolNameShort = "",
+        type = MailboxType.STUDENT,
+    )
+
+    private fun getStudentEntity(
+        studentName: String,
+        userName: String,
+    ) = Student(
+        scrapperBaseUrl = "http://fakelog.cf",
+        email = "jan@fakelog.cf",
+        certificateKey = "",
+        classId = 0,
+        className = "",
+        isCurrent = false,
+        isParent = false,
+        loginMode = Sdk.Mode.API.name,
+        loginType = Sdk.ScrapperLoginType.STANDARD.name,
+        mobileBaseUrl = "",
+        password = "",
+        privateKey = "",
+        registrationDate = Instant.now(),
+        schoolName = "",
+        schoolShortName = "test",
+        schoolSymbol = "",
+        studentId = 1,
+        studentName = studentName,
+        symbol = "",
+        userLoginId = 1,
+        userName = userName,
+    )
+}