I cannot hear anything when calling/receiving through the phone. I have to use bluetooth or earphones to hear. Please help me to resolve this problem. The speaker function is working properly.

Welcome to the forums.

Most likely you have a defective earpiece speaker. They have been known to be a problem. It should be covered under warranty by TMo if it's less than a year old.

Welcome to the Forum.

It sounds like the internal speaker is having problems. Have you pulled the battery (while powered on) and let the device reboot?

Plug the earphone in and out rapidly a few times, sounds like the internal plug is dusty and holding contact when the plug is removed. Blow it out with canned air or a compressor and give it a try.

Use caution and hold canned air 100% upright do not tip it and spray liquid condensed in the can into the plug.

thank you guys for the input.
the phone is not under cover with warranty. I have updated the firmware, wipe handheld feature, and reset the phone but the problem still persist.

i dont have Tmobile anymore. but my friend has it. is it possible that he can put this phone to his account and call in say that it is dead?