Date field data keep dissappearing

Date field data keep dissappearing

I previously sent in a support ticket, but no one seems to be responding.

I have a custom date field I have been using for a  while now. However I just noticed that the data is missing, every time you enter a date - it disappears. I have lost some critical dates now since I have no other record other than ZOHO on the custom date.

Can someone please advise me what might be happening ?