You may see a 'Insufficient Balance' when trying to register a name.
Possible reasons for this are:
The connected wallet is different the one you intended and doesn't have enough ETH.
The connected wallet does not have ETH on L1 Ethereum mainnet
Slightly more ETH is needed to cover any possible price fluctuations (any unused is returned)
Solution:
Check your connected wallet is the correct one
Check you have ETH on Ethereum Mainnet
Top up you wallet with more ETH
Registration, renewal and gas fees are paid in ETH on the Ethereum mainnet.