RPC errors typically occur because of a configuration changes or connection issues between the wallet and app.
Or
It might also be because you have insufficient ETH in your wallet
If you are seeing this when trying to Extend a registration or you're trying to complete the second 'Register' transaction, double check you have enough ETH on mainnet Ethereum. We’re working on making the message clearer.
Note: If your ETH is on a Layer 2 (e.g., Base or Optimism), it won’t count toward this action. Transferring enough ETH to mainnet will fix it.
Solution(s)
Double check your balance, and top up the ETH on Mainnet Ethereum if necessary. Otherwise;
Clear the browser cache and cookies for ENS App, and update both your browser and wallet.
If the error persists, you might look to change the RPC of your wallet - the support page of your wallet should have a guide on changing the RPC.
Change to a different wallet entirely.