diff --git a/mc_backend/mcserver/app/api/corpusListAPI.py b/mc_backend/mcserver/app/api/corpusListAPI.py
index c765bff78a8a47442ccdb5e89721ccb63a24942d..7f9845c6117f512d23e5d3f353005dde69775e9f 100644
--- a/mc_backend/mcserver/app/api/corpusListAPI.py
+++ b/mc_backend/mcserver/app/api/corpusListAPI.py
@@ -21,5 +21,6 @@ def get(last_update_time: int) -> Union[Response, ConnexionResponse]:
         return NetworkService.make_json_response(None)
     if ui_cts.last_modified_time >= last_update_time / 1000:
         corpora: List[Corpus] = db.session.query(Corpus).all()
+        db.session.commit()
         return NetworkService.make_json_response([x.to_dict() for x in corpora])
     return NetworkService.make_json_response(None)
diff --git a/mc_backend/mcserver/app/api/exerciseAPI.py b/mc_backend/mcserver/app/api/exerciseAPI.py
index 67c54ca70dbac9977c49ef996f95a9d017d804de..5675c184a95adf082aee37f0e784b23bfcd5f76d 100644
--- a/mc_backend/mcserver/app/api/exerciseAPI.py
+++ b/mc_backend/mcserver/app/api/exerciseAPI.py
@@ -27,6 +27,7 @@ def adjust_solutions(exercise_data: ExerciseData, exercise_type: str, solutions:
 
 def get(eid: str) -> Union[Response, ConnexionResponse]:
     exercise: TExercise = db.session.query(Exercise).filter_by(eid=eid).first()
+    db.session.commit()
     if exercise is None:
         return connexion.problem(404, Config.ERROR_TITLE_NOT_FOUND, Config.ERROR_MESSAGE_EXERCISE_NOT_FOUND)
     ar: AnnisResponse = CorpusService.get_corpus(cts_urn=exercise.urn, is_csm=False)
diff --git a/mc_backend/mcserver/app/api/exerciseListAPI.py b/mc_backend/mcserver/app/api/exerciseListAPI.py
index 0270c6533c7fd9684b06ec11ce34c2fc3caee411..36a91b40b401af2064f1da9a02667b4352aa5ea1 100644
--- a/mc_backend/mcserver/app/api/exerciseListAPI.py
+++ b/mc_backend/mcserver/app/api/exerciseListAPI.py
@@ -34,6 +34,7 @@ class ExerciseListAPI(Resource):
         last_update: int = args["last_update_time"]
         ui_exercises: UpdateInfo = db.session.query(UpdateInfo).filter_by(
             resource_type=ResourceType.exercise_list.name).first()
+        db.session.commit()
         if ui_exercises.last_modified_time < last_update / 1000:
             return NetworkService.make_json_response([])
         try:
@@ -47,6 +48,7 @@ class ExerciseListAPI(Resource):
         except ValueError:
             lang = Language.English
         exercises: List[Exercise] = db.session.query(Exercise).filter_by(language=lang.value)
+        db.session.commit()
         ret_val: List[dict] = [NetworkService.serialize_exercise(x, compress=True) for x in exercises]
         matching_degrees: List[float] = []
         if len(vocabulary_set):
diff --git a/mc_backend/mcserver/app/api/fileAPI.py b/mc_backend/mcserver/app/api/fileAPI.py
index ae2c604de2eef37f48db2a2c70e4b62bbb0546f8..3df739907326842468040511ea9e495dd3743c58 100644
--- a/mc_backend/mcserver/app/api/fileAPI.py
+++ b/mc_backend/mcserver/app/api/fileAPI.py
@@ -44,6 +44,7 @@ class FileAPI(Resource):
         args = self.reqparse.parse_args()
         eid: str = args["id"]
         exercise: Exercise = db.session.query(Exercise).filter_by(eid=eid).first()
+        db.session.commit()
         file_type: FileType = FileType[args["type"]]
         file_name: str = eid + "." + file_type.value
         mime_type: str = MimeType[file_type.value].value
diff --git a/mc_backend/mcserver/app/api/h5pAPI.py b/mc_backend/mcserver/app/api/h5pAPI.py
index cca14b68483b6a536cf8237c0e33df857715b571..ac5ea9921b1717f5aad13123fc9263bbc9efc555 100644
--- a/mc_backend/mcserver/app/api/h5pAPI.py
+++ b/mc_backend/mcserver/app/api/h5pAPI.py
@@ -73,6 +73,7 @@ class H5pAPI(Resource):
         except ValueError:
             lang = Language.English
         exercise: Exercise = db.session.query(Exercise).filter_by(eid=eid).first()
+        db.session.commit()
         if exercise is None:
             abort(404)
         text_field_content: str = ""
diff --git a/mc_backend/mcserver/app/services/corpusService.py b/mc_backend/mcserver/app/services/corpusService.py
index a7b3a669e51c1a08677b28f4dc734c92bc263b30..4bd1833b67fd972a77b8987e625495fa3bae81a7 100644
--- a/mc_backend/mcserver/app/services/corpusService.py
+++ b/mc_backend/mcserver/app/services/corpusService.py
@@ -338,6 +338,7 @@ class CorpusService:
     def update_corpora():
         """Checks the remote repositories for new corpora to be included in our database."""
         CorpusService.existing_corpora = db.session.query(Corpus).all()
+        db.session.commit()
         resolver: HttpCtsRetriever = HttpCtsRetriever(Config.CTS_API_BASE_URL)
         # check the appropriate literature for the desired author
         resp: str = resolver.getCapabilities(urn="urn:cts:latinLit")  # "urn:cts:greekLit" for Greek
@@ -373,6 +374,7 @@ class CorpusService:
                 db.session.delete(corpus_to_delete)
                 db.session.commit()
         CorpusService.existing_corpora = db.session.query(Corpus).all()
+        db.session.commit()
 
     @staticmethod
     def update_corpus(title_value: str, urn: str, author: str,
diff --git a/mc_backend/mcserver/app/services/databaseService.py b/mc_backend/mcserver/app/services/databaseService.py
index 11867a81857dbd07d5d5ad66f3ef638f09bf5ba5..2665027ffc2ca883fc2feb33e1c5d5029dd236a5 100644
--- a/mc_backend/mcserver/app/services/databaseService.py
+++ b/mc_backend/mcserver/app/services/databaseService.py
@@ -43,6 +43,7 @@ class DatabaseService:
         """Initializes the corpus list if it is not already there and up to date."""
         if db.engine.dialect.has_table(db.engine, "Corpus"):
             CorpusService.existing_corpora = db.session.query(Corpus).all()
+            db.session.commit()
             urn_dict: Dict[str, int] = {v.source_urn: i for i, v in enumerate(CorpusService.existing_corpora)}
             for cc in CustomCorpusService.custom_corpora:
                 if cc.corpus.source_urn in urn_dict:
@@ -59,6 +60,7 @@ class DatabaseService:
                                              group_name_value=cc.corpus.author,
                                              citation_levels=citation_levels)
             CorpusService.existing_corpora = db.session.query(Corpus).all()
+            db.session.commit()
 
     @staticmethod
     def init_db_update_info() -> None: