I've looked around in the community about locking or freezing a current date, but I'm still having issues.

That if i have marked tick on cell "C2 then today's date "11-11-2020" will auto populate into cell D2 i.e,. 11-11-2020 and that date will automatically changed to 12-11-2020 on very next day. Because of =TODAYS() function.

My goal is to lock a date that's triggered by marking a tick and have that current date freeze until the tick is removed.

My current sheet below shows the 10-11-2020 date which will change tomorrow and needs to be "locked" once the tick is marked and remain 10-11-2020 until the tick is removed

Could anyone help me correct formula to what it needs to be?

=IF(C2="Checked",TODAY(),"")