Quote

If you have "0" balance on GUI wallet and it's not updating, then you need recovery your wallet with mnemonic seed.

Open GUI wallet > Settings > Seed & Keys > Enter your password > Copy Mnemonic seed words on top

After that open Settings > Close wallet > Choose language > Restore wallet from keys or mnemonic seed > Follow instructions

That solution 100% will fix issue

Guys if you have problem with wallet balance, please do that instruction: