It may happen that saved path restrictions are no longer available after a restart.
You can correct this error as follows:
1. search in the transport network for the connection(s) where the restrictions are not saved
2. select the "Delete waypoints and connections" option (see screenshot)
3. there are now several connections. Delete all connections except the last one (which will be automatically blocked if a route passes through this connection).
4. Restart ipolog and open the scenario again.
You should then be able to save the restrictions again.