Could be 101 reasons. The only thing you can check quickly yourself is to plug it out, take off the top of vcr (usually 4 screws, two on each side and maybe two or three at the back),and check if there is something physically stopping the tape from going down into position in the carriage....e.g. a piece of the label which has come unstuck from a tape or a kids toy etc. Other than that it`s probably a fault in the machine like the mode switch or the carriage unit which would not be worth getting repaired anymore.