Roof still leaking after repair

[Asimy]

Had a leak in my flat above the window (not the window seal) so called a roofer to check the problem who had advised the guttering has lots of moss and needed clearing and the ridge tiles on the roof had gaps in between and needed re-cementing and repointing.

Had the person come and do the job the next day however the person living at the flat reported there is even more water leaking now during heavy rain so I contacted the roofer who advised it can't be leaking and it is most likely due to water that was already built up previously but then why would it start leaking after rain only? and advised to leave it for 3 days if its still leaking to contact him back

At this point i am feeling like i have been ripped off and it wasn't the ridge tiles all along and something to do with the gutter pipes? why would the leak have increased after the guttering was cleaned.

Could I have your thoughts on this people

 

[opps]

It could be a number of things, for example, the volume of rain being too great for the gutter to cope with. It seems unlikely that the gutter volume has suddenly become insufficient but it is possible that the downpipe is blocked. Blockages tend to be at the bottom. Perhaps try pushing a hose pipe up and see if you can find an obstacle.