diff --git a/common/db.py b/common/db.py
index 3987651..684febb 100644
--- a/common/db.py
+++ b/common/db.py
@@ -17,6 +17,10 @@
 import mongomock
 import grpc
 from ensembl.production.metadata.grpc import ensembl_metadata_pb2_grpc
+from graphql_service.resolver.exceptions import (
+    GenomeNotFoundError,
+    FailedToConnectToGrpc,
+)
 
 from common.utils import process_release_version
 
@@ -36,9 +40,10 @@ def __init__(self, config):
         self.config = config
         self.mongo_client = MongoDbClient.connect_mongo(self.config)
 
-    def get_database_conn(self, grpc_model, uuid, force_grpc=False):
+    def get_database_conn(self, grpc_model, uuid):
         grpc_response = None
-        chosen_db = self.config.get("mongo_default_db")
+
+        chosen_db = None
         # Try to connect to gRPC
         try:
             grpc_response = grpc_model.get_release_by_genome_uuid(uuid)
@@ -47,23 +52,21 @@ def get_database_conn(self, grpc_model, uuid, force_grpc=False):
             logger.debug(
                 "[get_database_conn] Couldn't connect to gRPC Host: %s", grpc_exp
             )
+            raise FailedToConnectToGrpc(
+                "Internal server error: Couldn't connect to gRPC Host"
+            )
 
-        if force_grpc:
+        if grpc_response and grpc_response.release_version:
             chosen_db = process_release_version(grpc_response)
         else:
-            if grpc_response and grpc_response.release_version:
-                chosen_db = process_release_version(grpc_response)
-            else:
-                # chosen_db value will fall back to the default value, which is 'mongo_default_db' that is in the config
-                # if force_grpc is not True
-                logger.warning(
-                    "[get_database_conn] Falling back to the default Mongo DB: '%s'",
-                    chosen_db,
-                )
-
-        logger.debug("[get_database_conn] Connected to '%s' MongoDB", chosen_db)
-        data_database_connection = self.mongo_client[chosen_db]
-        return data_database_connection
+            logger.warning("[get_database_conn] Release not found")
+            raise GenomeNotFoundError({"genome_id": uuid})
+
+        if chosen_db is not None:
+            logger.debug("[get_database_conn] Connected to '%s' MongoDB", chosen_db)
+            data_database_connection = self.mongo_client[chosen_db]
+            return data_database_connection
+        raise GenomeNotFoundError({"genome_id": uuid})
 
     @staticmethod
     def connect_mongo(config):
diff --git a/graphql_service/resolver/exceptions.py b/graphql_service/resolver/exceptions.py
index 8df3053..66e002f 100644
--- a/graphql_service/resolver/exceptions.py
+++ b/graphql_service/resolver/exceptions.py
@@ -235,7 +235,7 @@ def __init__(self, message: str):
         super().__init__(message)
 
 
-class FailedToConnectToGrpc(grpc.RpcError):
+class FailedToConnectToGrpc(GraphQLError):
     """
     Exception raised when there is gRPC connection issue.
     """
@@ -246,4 +246,5 @@ def __init__(self, message: str):
         Args:
             message: The error message describing the issue.
         """
-        super().__init__(message)
+        self.extensions = {"code": "SERVER_CONNECTION_FAILED"}
+        super().__init__(message, extensions=self.extensions)