I had a similar problem. See post FP2 Won’t turn on or charge - See first post for troubleshooting
From all I gathered in the forum, I was sure that my bottom module was broken. Support figured it was the battery. They sent a new one (after 1 month) and it did not change a thing. With the new charged battery the phone worked, until the battery was empty. Still no charging and the red blinking light. So again I told them that I was sure the problem lies in the bottom module. They did not want to send me a new module, but wanted to repair the phone themselfes. I can understand this; they do not want to send out “free” spare parts because some strangers believe they will help. But in my case it was a pain in the ass. The repair-place (it is apart from the normal support) told me that they would definitely delete all my data and I should make a backup. But how am I to do this, if the phone is not working at all??? I contacted my “normal” contact person and she told me, the data will not be deleted. Who am I to believe? Luckly I trusted the technical support. So I had to buy an external charger to charge my battery (on my cost, but they are cheap, crappy pieces childlabour-electronics). Then I could do my backup. I sent the phone to the fairphone repair and got it back 2 weeks later with a report stating: Bottom module replaced. Of course they deleted all my data for privacy reasons.
So, in short:
- You should contact support and they will help you. They are very friendly, but slow. Which is annoying, because people rely on a phone (I was back on my 10-year old phone for 2 months…).
- Test to charge your battery with an external charger or a fairphone from somebody else. If it charges, the bottom module is likely broken. If it does not charge, it is likely a broken battery.
- If you sent in the phone for repair, make a backup before. They will delete your data.
- You should not buy spare parts on your cost, this is normal warranty.
- Prepare a bathtub of green tea, buy a rubix-cube and try to solve it just by yourself (no help from the internet!). You will have time to cover and should stay relaxed.