A while ago I had problems restoring my Blixt wallet.
The great @DarthCoin tried to help me, although I was unsuccessful, however he recommended that I contact the developer hampus in the Blixt group on telegram.
I was able to talk to hampus and discovered that the problem originated in the backup file of the lightning channel.
When I made my backup when I created the LN channel, I saved the file in Proton-drive. Then when it was my turn to restore the wallet, I downloaded the file normally from Proton and went on to try to restore the wallet without success.
As you can see, the original file weighs 132B and on the contrary, the file downloaded from Proton ends up on the device with a size of 45B.
Hampus told me that the file must weigh at least 100B in order for the restore to be able to be performed normally.
And in this case, that is the problem, the file being 45B is not enough to perform the restore.
However, restoring and selecting the file directly from Proton-drive does not work. And as I already mentioned when I download the file to the phone, to perform the restore with the file from the device, it is downloaded weighing 45B instead of the original 132B.
If you are reading this, I would appreciate it if you could contribute something that would help solve this problem.