paint peeling

The previous owner of our house must have painted the wall in some sort of semi gloss latex paint. When scuffed in the move we noticed it’s easy to scrape off. Not sure what to do as scraping a hall to landing floor is a big job. Do you think I could prime this with something?

Hi everyone, I moved into an old 1900s property recently and I DIY repainted the walls about 3 months ago. Most of the painting was directly onto the old paint and other parts on the old plaster directly where the old paint peeled off or sanded off. Today I am seeing bubbling in a few parts...

The paint on this side of the chimney breast keeps bubbling up. What can I do to remedy that please ? Ground floor flat in house built maybe 1900 Thanks