New door seal not sealing.

I have a 70cm wide Leibherr fridge freezer with the freezer section on top from approx. 1999. I recently ordered a replacement seal quoting model number etc, but the seal I received didn’t fit. I was subsequently told the seal is no longer available for my fridge freezer so I purchased a universal seal instead. I have now fitted the seal but the door doesn’t close properly, the top corner opposite the hinges has a large gap. I have tried loosening the top hinge and adjusting but made no improvement. It is as if the door is twisted. I would be rally grateful for some advice. Cheers Ian.