Is there a way to prevent players from being registered to two teams in the same club and same league?

Our league rules state that players may only be registered to one team in our league in the same age group. Yet as a league registration officer there is an alarming number of players that are being duplicated to teams.
This could be due to how a club/team register their players and I believe that one particular club are just adding the player to another team, instead of cancelling a registration.
The main issue is that this duplicate registration does NOT show up as already being registered and just shows as a new registration.

This never used to be the case and it may be that the league need to reset some settings.

As one of a handful of registration officers, we don't have the time to go in to every registration to double check each and every registration details.

Thank you in advance.