diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeTeachers.kt b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeTeachers.kt
index f2fdfe40..e9f209a3 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeTeachers.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeTeachers.kt
@@ -4,12 +4,12 @@
 
 package pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.data.hebe
 
-import pl.szczodrzynski.edziennik.DAY
 import pl.szczodrzynski.edziennik.data.api.VULCAN_HEBE_ENDPOINT_TEACHERS
 import pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.DataVulcan
 import pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.ENDPOINT_VULCAN_HEBE_TEACHERS
 import pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.data.VulcanHebe
-import pl.szczodrzynski.edziennik.getString
+import pl.szczodrzynski.edziennik.ext.DAY
+import pl.szczodrzynski.edziennik.ext.getString
 
 class VulcanHebeTeachers(
     override val data: DataVulcan,
diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/data/db/migration/Migration96.kt b/app/src/main/java/pl/szczodrzynski/edziennik/data/db/migration/Migration96.kt
index 52f77256..e8315aa3 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/data/db/migration/Migration96.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/data/db/migration/Migration96.kt
@@ -10,6 +10,6 @@ import androidx.sqlite.db.SupportSQLiteDatabase
 class Migration96 : Migration(95, 96) {
     override fun migrate(database: SupportSQLiteDatabase) {
         // teachers - associated subjects list
-        database.execSQL("ALTER TABLE teachers ADD COLUMN teacherSubjects TEXT NOT NULL;")
+        database.execSQL("ALTER TABLE teachers ADD COLUMN teacherSubjects TEXT NOT NULL DEFAULT '[]';")
     }
 }
diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/ui/teachers/TeachersListFragment.kt b/app/src/main/java/pl/szczodrzynski/edziennik/ui/teachers/TeachersListFragment.kt
index 8c24e111..09d79e08 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/ui/teachers/TeachersListFragment.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/ui/teachers/TeachersListFragment.kt
@@ -48,7 +48,7 @@ class TeachersListFragment : Fragment(), CoroutineScope {
 
         val adapter = TeachersAdapter(activity)
 
-        app.db.teacherDao().getAllTeachers(App.profileId).observe(this@TeachersListFragment, Observer { items ->
+        app.db.teacherDao().getAllTeachers(App.profileId).observe(viewLifecycleOwner, Observer { items ->
             if (!isAdded) return@Observer
 
             // load & configure the adapter