Discrepancy in static site from browser when viewed from domain vs from IP

When I make any changes on the static html file served by apache2 on my aws ubuntu instance, and when I see the site page from the domain name like abc.com, it is not getting reflected or it gets reflected with some delay of a few hours.

but when I visit the same page, with the elastic IP associated with that EC2 instance then I can see the change.

what could be the reason for this?

The File is served on EC2 instance with EBS store.