UV = unlimited hotspot
NX = including hotspot

😂

That thought has come to my mind, coz I've to help a friend with his account next, and it's an Oppo phone. 

I encountered the problem because I've never used Face ID on my iPhones all this while, though I knew it's an option before. It's until now that I needed it for the CelcomDigi app that I activated it.

Now I've to figure it out on that Oppo phone. 

If your phone has an option for Biometric Unlock (Face ID and/or Fingerprint or maybe even voice), then I guess it'd help. Otherwise might have to visit a Digi Centre for help.

No FaceID then use fingerprint, for sure there will be a biometric feature on your phone unless you are using a super old smart phone.