diff --git a/features/cellular/framework/AT/AT_CellularNetwork.cpp b/features/cellular/framework/AT/AT_CellularNetwork.cpp
index bd3ef20f2e..161128ab0c 100644
--- a/features/cellular/framework/AT/AT_CellularNetwork.cpp
+++ b/features/cellular/framework/AT/AT_CellularNetwork.cpp
@@ -224,7 +224,7 @@ nsapi_error_t AT_CellularNetwork::set_registration(const char *plmn)
         if (_op_act != RAT_UNKNOWN) {
             return _at.at_cmd_discard("+COPS", "=1,2,", "%s%d", plmn, _op_act);
         } else {
-            return _at.at_cmd_discard("+COPS", "=1,2", "%s", plmn);
+            return _at.at_cmd_discard("+COPS", "=1,2,", "%s", plmn);
         }
     }
 }