Sideloaded apps stop working when Apple revokes the developer certificate (often within 7 days for free developer accounts).
To summarize your options:
If your iOS 12.5.5 device is jailbroken or utilizes specific core exploits, you can use . TrollStore permanently signs IPA files so they never expire, providing the closest experience to an App Store install. Check TrollStore's official GitHub documentation to see if your device chip architecture is supported on iOS 12.5.5. Alternatives to Installing the App facebook ipa for ios 1255