Dear SuvaUV,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
Based on your description, it seems you don’t want End date column to take the previous date. I hope my understanding is clear.
If so, I tested from my side and below are my test results:
In a SharePoint list, Add Column > More > Enter Column Name >select Date and Time > Expand Column Validation > in the formula bar, enter =EndDate>=TODAY() and click OK as demonstrated below:
Then after, go to add column items in the field. A per my test when I enter yesterday’s date in the EndDate column, It will display an error, and if I choose tomorrow as End Date, the column saves with out any error, as shown in the screenshot below:
If my understanding is inconsistent with yours, please feel to post back and point it out. We will try our best to help you.
Thanks for your understanding and cooperation. We look forward to your reply.
Sincerely,
Edwine | Microsoft Community Moderator
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