As mentioned below by AppleFanBoy1982:
This is a known issue with apple. Here is the workaround: https://support.apple.com/en-us/HT205222
Origional post:
I updated to the beta 5 this evening, but have lost the ability to use Cellular data. This happens both with an over-the-air upgrade and a clean restore.
Am running on an iPhone 5C (Model A1456, A1532) using the Petro Canada network (Rogers reseller) in Canada.
APN name: internet.com
User Name: wapuser1
Please note this worked all previous betas and iOS 8.4