Why is NOW UTC incorrect time format? It has worked fine before!

I have never seen this error before but it is now coming up and stopping me saving any date time. I have this throughout my app.

How do I fix this?

status	"500"
code	"ER_TRUNCATED_WRONG_VALUE"
message	
stack	"Error: ER_TRUNCATED_WRONG_VALUE: Incorrect datetime value: '2021-07-28T22:45:53Z' for column 'date_created' at row 1