Aukey ep t25 working good on the phone but not on PC

Hello my brand new aukey ep t25 are working percetly when paired to my phone; but they are not working when i try to use them on my PC: the audio is very bad, i can listen 1 word out of 10.
I don’t understand if it’s an issue about bluetooth, about the earphones, about the PC or what…
can you help me?

thank you