iOS Build stuck on Waiting

Been using cloud build for a couple of weeks. Recently all my builds (of different games) are not getting installed on the devices.

When the user tries to install the build from Safari, an icon is created on the phone but it is forever stuck in "Waiting". The installation progress doesn't move.

What could be the reason? I have checked the provisioning profiles and everything to see that the device udid is added. It shouldn't be certificates/signing related because previous builds with the same setup were working fine.

Unity Version 2017.3
Collaborate used for Source Control