universal remote will not operate Matsui TVR185A?

I lost the original remote, got a universal one, the seller said it would not need a code. It will not operate the TV, I went back to him and he said it must have a child lock on!!! He said he has sold loads for this TV and no problems. I have been to tech guys, curries, dixons, who manufactured the TV, they were no help at all. I have no manual and cannot find one on the internet...please help!!! Does it need a code?