Yeh can anyone help me with my patio doors have a crack at the top of the centre of the frame and the frame is bowing how do I repair? :'( :'( :'( ??? ???
If its just a cosmetic crack then you could use "pvcu gap filler" from SOUDAL which fills and hides joints in pvcu and bonds pvcu components.
http://www.allfix.co.uk/Products/002a007d0337/%252ASOU111324
If its a major structural crack then you might need to replace the door.