diff --git a/src/caosdb/apiutils.py b/src/caosdb/apiutils.py
index 5fff7fd9312cbebfa52f38a982fdc7f58ee7c9cb..495941b517940b45e0e722b1534e313dc64dc487 100644
--- a/src/caosdb/apiutils.py
+++ b/src/caosdb/apiutils.py
@@ -30,7 +30,7 @@ import os
 import random
 import sys
 import tempfile
-from collections import Iterable
+from collections.abc import Iterable
 from subprocess import call
 
 from . import (BOOLEAN, DATETIME, DOUBLE, FILE, INTEGER, REFERENCE, TEXT,
diff --git a/src/caosdb/common/models.py b/src/caosdb/common/models.py
index 8fda13cf3afd119ec168917d75ea871c5f1772ab..1a600e05bbda957429931f5886e04ace32f025be 100644
--- a/src/caosdb/common/models.py
+++ b/src/caosdb/common/models.py
@@ -1617,6 +1617,7 @@ class _Properties(list):
         if isinstance(prop, Entity):
             if prop in self:
                 list.remove(self, prop)
+                return
             else:
                 if prop.id is not None:
                     # by id