How to network unlock the LG K7 from T-mobil?

[AC Question]

Hi, I just bought the LG K7 from T-mobil but I am now in France and need to use my French SIM card. The requirements from T-mobil to network unlock the phone are not okay for me (I have to wait for 3 months and pay 100 dollars!). Is there another option possible? Apparently I would need a code AND a special application if I have well understood. Thank you for your help!