Anonymous participant it’s their responsibility to report. Did they provide a valid reason why they didn’t do that?

you can also call immigration officer to consult your case or/just ask for clarification about the fine. This phone number you can find on immigration website.

First thing your previous landlord must report TM30 within 24 hours of your arrival, it’s their responsibility. Failure to report within the 24-hour window can result in fines for the landlord and yes you may face difficulty getting your visa extended if your TM30 record isn't up to date and have to pay the fine up to 1,600 THB to the officer.

For your current apartment if it’s different landlord, different place, it has nothing to do with them they just have to report within 24 hours the same otherwise you will face the same problem. Make sure to request the proof of TM30 report within 24 hours after your move in.