A new account that has been added to your Accounting System will be brought through to Calxa on the next Sync. If you cannot see the account in the Budget screen:
From the Budget screen, use the E on the keyboard to toggle off/on Empty Rows
Run a sync manually using the Sync Now option Reports > Report Tools
If you are using an Account Tree in the Budget screen scroll down the Accounts to find any new / unallocated accounts at the end of the list