Logic Pro X - project tracks stopped being in synch

I have been working on a song (project) for several weeks. My input device is an UA Apollo Twin X. The project was working fine until a few days ago. Suddenly every track is out of synch with each other, one of my 2nd takes stops the entire project, then starts, but is out of time/synch. Further, a software instrument that was previously in tune is no longer in tune with the song.

Don't know why this has happened. I used to be able to have it play whether or not it was attached to my Apollo. For example, I would make some edits with only my laptop.

I have reviewed a number of websites and youtube videos, but the suggestions of changing the buffer, reducing latency and other suggestions have not worked. Very frustrated because I have put a lot of work into my song, and was getting ready to record the final/main vocal and tidy it up to send out to my band to play live.

Please help. Let me know if you need more information.

Thanks very much,

Brendan