An access point is needed to send or receive SMS/MMS on the Oppo-Smartphone. Mobile data also needs a correctly configured access point. APN data is usually configured after dialing into the network, but can also be added manually.
- Open the Settings
- Tap on SIM card & mobile data
- Choose desired SIM card
- Tap on Access point name
- Tap on Add
- Set up APN and confirm with Save