If you have sync, and there is a problem anywhere, Shut Down Sync Immediately On All Devices to prevent the problem from spreading. Once the problem is fixed, perform the same repair on all computers/profiles before using sync again.

The simple way: Can you Copy the password files from the cell to the computer?

logins.json and key3.db [v58+]key4.db : These are the password files. Copy Both ! to your Firefox profile, overwriting the current.

Thanks for the reply. I already stopped sync. I cannot access those files in my android device, they are not accessible. Now I have no login data on my computer, and I want to recover that data from my android phone. Shall I create a new account on my android and connect it on my computer? Would that work?

This is what you are going to do. 1) Close the current sync account.

2) Using your cell, create a new account. Leave the browser open for a while so the data gets synced.

3) Once you are sure the servers have the data, have the computer log into the new sync.

4 Cross your fingers, your toes, your eyes . . . .

I followed the steps you described and created an account on android device and then linked it to firefox on computer. The login data doesn't sync, it remains in the device but is not synced with the computer. So it's a sync problem and I don't know how to resolve this.