My FP4 wants to update to Software FP40.A.0142, Security patch level: 5th of June 2022. Yet it tells me, that it cannot download due to too little space (needs 529 MB). But I have several GB unused space.
Strange thing: When I check Build number of the currently installed System it tells me FP4.FP40.A.142.20220628. This is actually an newer build than the one it wants to install…
Clearly you have used maybe a lot of memory. You can try adding an SD card formatted as Portable and move some|all you media (music, photos and videos) to the SD card. This will free up some space and hopefully the warning will not appear.
I do have the 128MB model. Yet this cannot be the issue as no Model could do an update of 529MB if this was true.
Regardin space: I’m just telling you what my phone shows me - and this is lots of free space. Moreover I am carefull with regularly deleting app caches and pics/vids I have sent to my cloud. In addition I only stream music and videos from my server - no download…
Even if that’s possible I think it’s best to correct the problem at source. You may be seeing just a side effect of something potentially more problematical.
Make sure you have up-to-date back-ups of everything important.