About 90 days report again

Firstly, sorry for my english

Hello all, i've a question about 90 days report.

I have ED visa for 15 months but because in the laws you can't do more than 9 months, i leaved Thailand and come back for my last 6 months.

I still keep the same condo since the start so i tought i just have to wait 3 months for make the 90 days-report.

The problem is my school, they tell me i have to ask my landlord for give the prove of a complete TM 30, i ever do the first time (my landlord didn't report me the first time, so i think she payed a fine).

So i didn't know if it's my fault because i didn't told my landlord about my new ED-Visa ? She didn't ask me anything so maybe she didn't report since i come back with my new visa (3 months), no copy of my new departure card etc...

She will have to pay fine again ? It's my fault to didn't tell her ? Or it's problem of her to knew that ?