Categories missing from monthly budget tab

Some categories and transactions are missing. It appears I have caused errors by not inserting new Categories to the bottom of the sheet and inserting them otherwise. The suggestion I received from Tiller support is to download a new template and recreate my categories. I have several months of data to manage. Is there an efficient way to do this without starting over? Thank you.

My suggestion would be to Troubleshoot the Category dropdown in the Transactions sheet and then use the Data Checker Tool. Let me know if you have any questions.