I think you need to call support as for help as to why it is saying you have used all your returns when you did not.

If you just hit transfer all then it would bring the non returning clients as well. If you went into 2023 and deleted the non returning clients then hit transfer you would only have active clients. Or you could have hit select all then unchecked the non returning.

You can highlight and delete individual clients from the homescreen - might take some time but you can get rid of them