Solution:
1. Make sure that the newly uploaded files already exist in the Document Library.
2. Re-index the search site and Document Library site to sync all newly uploaded files and to be displayed in Fotopia Search Pages.
3. If SharePoint is on-prem, access SharePoint server and perform Full Crawling on SharePoint sites from SharePoint Search Services Applications
4. Once full crawling is completed then you can check the SharePoint again to verify if files are appearing
5. In case the issue persist, raise a ticket to Fotopia support team to escalate it to a higher level.