Miles since last fillup wrong

[PWBarrett]

I've been worried my motorcycle was getting bad MPG the last several months.
Turns out it's Fuelly miscalculating. If I take the odometer readings and subtract previous from current, it's way more miles than what's showing in the "miles" column. If I use this alternate miles calculation, the MPG comes out just fine.
It was correct until 8/22/2019, where it looks like maybe I missed entering a fill-up and forgot to mark it. All 10 entries since that have the wrong delta-miles. I went back and marked that entry as missed-fillup, but it doesn't change anything.

Should I just start a new vehicle log?

[Lokhankin]

Similar issue happened with my "Jettka" (from web site):
previous fill-up - Odometer Reading 67798.0
current fill-up - Last Odometer: 68306.0
Calculated miles, driven between fill ups shown on the site - 148.00 !!!
Deleting the last record and creating it anew - didn't fix this issue;
Removing previous record didn't change the last one values
re-creating previous record - didn't do anything with the most recent fill-up results - showing the wrong miles between fill-ups.