Do you have a backup copy of your seeds and private key of the BTC address where you receive bitcoins?
If you still don't have a backup follow this guide below.
Backup seed:
- Open Electrum
- Click wallet upper left of the Electrum
- Click seed(Then put the password if it requires)
- Copy the seed and paste it somewhere safe or write it down to the piece of paper.
Backup private keys:
- Open Electrum
- Click "view" right side of the "wallet"
- Now click "show addresses"
- Click the addresses tab then find your bitcoin address where you receive bitcoins.
- Right click then click private key(Enter the password if it requires)
- Copy your private key then save it somewhere safe or in notepad for temporary.
Now you have a backup copy of your seed or the private key of the address where you should receive bitcoins.
Now install/upgrade the latest version of Electrum using this command line below.
wget https://download.electrum.org/3.3.5/electrum-3.3.5-x86_64.AppImage
chmod +x electrum-3.3.5-x86_64.AppImage
Now you can run it with this code.
./electrum-3.3.5-x86_64.AppImage
Now you have the latest version import your seed or private key and it should fix your problem.