Why when I answer my Bluetooth the call goes to speaker phone

You can install the Plantronics app "PLT Hub". That shows whether the headset has recognised that it's in your ear or not. If not, the call goes to the phone's speaker.

Sometimes it helps to place the headset on a non-metallic surface with the earpod point up while charging. This should re-calibrate the sensors.

HTH

Check the properties of the Bluetooth connection on your phone

Settings, Bluetooth, Connected Device settings.

There should be several check boxes related to functions that the connection can be used for. (Media audio, Phone audio, etc.)

I turned off the sensor and that did the trick for me.