Version Number Conflicts

We are the client of a vendor who built a custom app for us. We use mobile device management to automate application updates. We push 45 apps and 44 work flawlessly. The 45th is this app and we always have to manually force it to update which causes drastic issues when the app is updated. After troubleshooting, it appears there is some type of mismatch between the store version number and what the device sees. The store will show the app as 1.2.3.4 but the device shows 1.2.3 when I force it to update. The vendor shows that they fill out the version as 1.2.3 and the build number as 4 which then produces 1.2.3.4.

Are they filling this information out correctly? Are there other fields that are required for them to fill out elsewhere with the version number? Thank you

Version Number Conflicts
 
 
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