Screw retained implant crown was installed May 2016, re-cemented in May 2023. It continues to fall out. Options?

My screw retained implant crown was installed May 2016. January 2023 while getting my cleaning done, I was told it was loose. Dentist said he couldn't tighten it & broke it off. He said it came loose because he put too short of an abutment. Said he was re-doing so this wouldn't happen again.He re-cemented it in May 2023. Never discussed with me that he was cementing it and why. It continues to fall out. Now he says he wasn't able to use screw retained but never discussed with me.