Error 37 despite repair man replacing parts?

Hi, I got an error 37, found a block (Piece of peg) in pump, which was removed. Same error code. Repair man replaced diverter valve. Got same error code. Repair man came back replaced drain pump as it was only draining sometimes. Did two loads of washing ok. On third load however it stopped at the Rinse 1 cycle, wont drain, says same error message and makes a quiet wirrr sound like it is trying to do something. Please help as I'm getting really frustrated, I need a washing machine!!!!