Speeding up your 3G/LTE networks by the following tips:
Contact your network provider to check if there is problem with mobile network.
Install your SIM card on another phone to check if there is problem with your phone.
Access to Safe Mode, press and hold the power key then tap Power Off > OK. If your phone is working well in Safe Mode, that means there might be third-party apps that cause malfunction when you use in Normal mode.Please restart your phone and check again.