Precision 7540 doesn't charge via USB-C (Thunderbolt) port

Hello everybody,

I've owned a Precision 7540 since 2019 and a few weeks ago I bought a 100W GaN USB-C Power Delivery charger to use it on my machine when I'm out of the office, obviously for light tasks.

To my surprise and disappointment, the charger doesn't power the battery. When plugged into either of the two Thunderbolt ports, a message appears stating that the notebook is not charging. At other times, another message appears indicating that a charger with a minimum of 90W is required.

This makes no sense remembering that the charger is 100W Power Delivery!

I've already tested the charger on 2 other Dell Inspirons notebooks, 5402 and 5510, and on both it works perfectly, including delivering all the performance (both machines that have 65W chargers)...

Can someone help me?

I already changed Thunderbolt settings in the BIOS and nothing worked...

Do I have the 2 faulty Thunderbolt ports or is this just a Dell block against 3rd party chargers?

Both USB-C ports are often used with peripherals and with Display Port and work perfectly. The problem is only with the Power Delivery that Dell claims in the Precision 7540 manual supports up to 130W...

I hope to solve this problem without needing to call the warranty...