Hairline wall cracks (not external, only internal), block of flats from 60s

[paul2190]

Hi, I'm the owner of a flat in a block of flats, ground floor, this is the entrance to the door of my flat, you can see this long hairline cracks in the top left corner of the entrance door to my flat. The building is from the 60s and in the past, due to a tree very close to the building in the neighbours garden, there has been a claim for ground heave landslip. The issue was rectified and we were given also a certificate of structural adequacy, the neighbor told me they also injected resin for the building stability. Do these cracks look worrying to you? Many thanks in advance
https://ibb.co/K2bhp4s (link to the image)

 

[paul2190]

Above the door there's the door to the flat above, whose entrance door is developing similar hairline cracks. On the right of my door there's the block entrance door and on the left of it the stairs going up.