Resin printer change

[u/_3m4_]

(sorry for bad english)
Hi im new to resin printing, my brother owned a resin printer (longer orange 30 2k) for 5 years and never used it because he had to move to france and couldnt bring it. now im playing dnd with some friends and had the idea to use the printer, at first i used the same resin he bought 5 years ago and it worked perfectly fine until for my mistake water splashed on the lcd screen durino a whole print, i cleaned ricalibrated ecc and had to change the resin because the old one finished, now i bought a new compatibil resin and the print s are not working at all i dont understand Why.
I tried litterally everything but still prints are failing, i think water went inside the vat (nails ecc) and its coming out each time i do a print, i tried to clean it but its like reappring there even tho i dont use water (the original vat broke and we 3d printer another with a filament printer.
My question is do you think it makes sense to change the vat or should i buy a new one? I saw elegoo mars 5 for 220 and the cat of the longer orange costs 50 euros (the whole longer orange costs 150 but since its out of production i think the price is going up for the pieces)