The only thing I can think of is that only one of the 2 USB-C ports can be used for charging, namely the 60 watt port. Also, make sure that the charger has some power. It doesn't have to be 60 watts, but with very old 5 watt mobile phone chargers it didn't work for me either (not recommended anyway because of the long charging time).
Otherwise I would contact Digitec
Mfg Andi