If you notice that your mobile data is slow, it could may be fixed by choosing another network type.

Android 9
Network type -  Open the  settings
Network type -  Tap on  Network & Internet
Network type -  Tap on  Mobile network
Network type -  Tap on  Advanced
Network type -  Tap on  Preferred network type
Network type -  Choose a  network type 
  1. Open the settings
  2. Tap on Network & Internet
  3. Tap on Mobile network
  4. Tap on Advanced
  5. Tap on Preferred network type
  6. Choose a network type 

Android Instructions
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