So, I did. But no BTC in it.
@Sauaba Address aren't created and saved as you request one in the 'receive' tab.
Those are pre-generated as you created your wallet, it's just hidden by default. You can view them in the "Addresses Tab" (View->Show Addresses menu).
If you created an invoice and exit Electrum, the address that's shown in the Receive tab will use the next unused address.
You can also create multiple wallet in Electrum without deleting the others.
If the list shows a set of addresses that starts with different number/letter than your "saved address", then it's a different wallet.
Try to find if it's in your other wallet using "File->Open" menu.
The reason why bech32 address (bc1) is invalid was already answered.