Pay day and leave the country presume then the visa cancels itself or stick it out and leave near to its expiry if you resign they could cancel the visa without you knowing presuming they are your sponsor after you have left the country email them with a family emergency and say you are not returning
I had same situation and got a one year multi entry stamp at Hua Hin for thb 3800 very simple and valid for one year then 45 days before that expires you need to do a proper renewal bank state medical etc
Dont use booking.com you will find that despite it saying free cancel when you get to the pay page it says below the enter credit card details but out of sight that the booking cant be cancelled try agoda instead
