Can’t use my own data

I have plenty data, 2+ GBs, but I cannot connect to the internet. This has been inconsistently working / breaking for a week now and it makes no sense. It shows that I’m on Vodacom 3G or 4G but if I try use an app that needs data, it just says “no internet connection.” I avoid admin at all costs, but this has been frustrating enough to make me switch providers, especially since the help from Vodacom has been “have you rebooted?”