Each player is only allowed to play for one team during one season in one league.
A player who has played at least twice for each of more than one team is considered an irregular multi-team player and his game results are corrected according to Appendix D.
for checking multi-team player issues. Inform your players that they may play only for one single team in the WCL. Remove players from your roster who play for other teams as well.
From the rules (https://www.chess.com/clubs/forum/view/wcl-2023-rules):
6. Multi-team players
Please consult
https://chessteams.info/multiplayers.php#WCL2023
for checking multi-team player issues. Inform your players that they may play only for one single team in the WCL. Remove players from your roster who play for other teams as well.