MySql date error

I keep getting this error you can see at the top when trying to save a record (screenshot uploaded).

I found something in this forum about it and didn't understand so i just upgraded this site to the latest cmsb but that didn't help.

I can save the event when selecting "neverRemove". It also works if I set the remove date to 2020 for some reason.

This all started when the client ran out of dates that I had up to 2018. So I used the blank option in administration to make the last and next 5 years always available.

Thanks for any help.