when i turn my 22"TV on it works ok for about 15 minutes and then
the remote control control stops working the problem is not the remote because none of the buttons work on the tv after the remote stops working
As you say it's not the remote since the TV controls stop working too. Something in the TV heats up after 15minutes and the controls stop working. It might be repairable at the component level but not at the board level. Not a diy repair imo.
Given the size of the TV I would say that it's time to replace it.