Gmail Mobile App Zoho IMAP Missing Messages

I recently migrated my email from Google Apps for Business to Zoho Mail. I have a custom domain with multiple email addresses. All of the migrations went well with no problems. Since the Zoho Mail Android app does not support multiple email addresses, I decided to use the Gmail Android app to access my Zoho Mail addresses using IMAP. For one of these addresses, I am missing a large chunk of messages in my inbox in the Gmail app only. They are visible in the web interface. The only way that I can get them to show up in the Gmail app inbox is to move them out of the inbox and back in to the inbox using the web interface. After moving the messages out and back in to the inbox, they will show up in my inbox on the Gmail app. So, is this a Gmail app problem? Or, is this a Zoho IMAP server problem? Or, did I mess something up while re-organizing my mail folders after the migration? Thank you in advance for your help.