Curious dates have appeared in my database synced to a Google sheet

[Ross McMillan]

I have a database on an Android phone which is linked to a Google sheet.

Occasionally the dates entered have the day and month swapped and I have to manually swap them back.  It has got worse now, however, and the dates on both the app and in the sheets have taken on crazy values, like 2 years in the future.

Is there any way I can recover from this?  Not all the dates are affected, and AFAIK I haven't lost any other data.

And (naturally) I would like to know how to prevent it in the future.

TIA