Looks like an overzealous manager
A guide to making your small block of flats safe from fire (accessible) - GOV.UK
4 Fire Hazards
Housekeeping
Good housekeeping is fundamental to reducing the risk from fire in the common parts. The common parts should be kept clear of any combustible materials or storage.
There should be a zero-tolerance approach, in which residents are not permitted to use the common parts to store any belongings or dispose of rubbish.
However, in well-managed, secure blocks, it is often acceptable to permit items of lower risk in the common parts, such as doormats, pot plants and pictures on walls.