My oven door won't shut on the lower oven ?

I have recently moved house but the oven door won't shut on the lower oven. I have replaced the hinges as suggested by the oven cleaner man but the situation has not improved.
Model: Bosch - HBN9320GB/01 white.

I guess its a few years old and I’m in two minds. Don’t really want to waste more money on it. Is it a simple fix or should i purchase a new one.

Thanks in advance

Scot R
May 2009