How to validate the wrong date time entry in SharePoint using column validation?

[288088]

I got these 3 fields in the form where in text form my colleges input date and time. But sometimes they put in wrong times in the fields, and I want a validation for that.

See the picture, if "Ärende påbörjat" is less than "Ärende tilldelad" and "Ärende tilldelad" is less than "Ärende inkommet" I want it to give a warning.

I also want it to be possible to leave the fields empty and save the form. I've tried myself but cant solve it.

[#2]

Hi,
Since this is SharePoint online, please use 'Customize with PowerApps' to edit the form and add branding, validation and other stuff.

Hope it helps, please like it or mark it as a solution if it resolves ur clarification or issue
-Sudharsan K...