Hey Farokh,
The Instagram display might be dependent the dimensions of its container. If the container is small, the Instagram display will also be small.
I see you’re using the Pro Footer Builder. Your Bar’s Height must be set to auto
.

Your Container’s Self Flex must be set to Fill Space so that it fills the width of the bar’s content.

And. the Text element you inserted your Instagram shortcode should have a Width of 100% so that the Instagram display will fill that up.

If that doesn’t help, please give us the URL of the page where this issue is happening and also your site’s WordPRess Login URL, username and password in a Secure Note.
Regarding the instruction Lely suggested, she presumed that you know how to code. If that is not the case, please disregard the instruction as working with custom code also is considered custom development and we do not cover support for issues that will arise from the use of it and further enhancements.
Thanks.