Possible Subsidence?

Hello everyone, i am new to this forum so please bear with me.
I have purchased a property as a buy to let over a year ago, i did a full building survey which picked up on the fact that the building either has subsidence or very bad settlement in its past.
I still purchased the property as i got a good deal, and hoped for the best that it was settlement. However recently the front upvc front door is sticking when i attempt to close it. It is sticking to its own frame and i have to slam it shut with enough force for it to actually close fully. The front window on the same face of the property is also abit stiff but does open and close well.

I know this is a very difficult question to answer without seeing the property, but in anyones opinion does this sound likely to be subsidence?

Thank you for any help or advice in advance.

Have you checked that the PVC door is still square likewise the window? If not fitted properly they droop down from the hinges. If the building has dropped enough to cause the door to stick, you should be able to see the cracks.
FWIW My last house ~ 100 years old, had a problem with heave around the front corner, causing the door to stick because the doorstep would rise in the winter. I planed a bit of the door and lived there for 32 years. When I sold it the surveyors made no comment on this feature!
Frank