NEFF, please help?

Hi. we have a NEFF fridge freezer.
the bottom of th efridge is collecting water rapidly, and seems to be freezing things that are put at the top back of the unit.The doors need a new seal, which is easy enough to do.However, the frrezer door hasnt been able to close properly for a while due to it over freezing. it has now gotten to the point that we cant even open the door fully as it has frozen up.
what do you recommend we do, as there is no way we can afford to replace it.