Thank you for your incredibly prompt response. I was just coming back here to update my post said that I found the issue. In this case, the previous entry had an incorrect mileage value which made today's entry lower than the previous one. The error trapping was entirely correct, but I did chase the possibility of the date being the issue for a while first.

Same issue here, but the entry is for today (Feb 3, 2026)!

I Have used this app for years on end but just bought the Pro version to scan receipts. Was wondering if this issue was connected to that upgrade.