Check the suitability of the docking station, the USB hub, etc.. I am using two Acer EB3321HQUC 32" monitors of the same type at two locations, each without flickering and with correct resolution, in combination with a Surface. At location 1, an official Microsoft Surface docking station is in use, at the other location a Targus DOCK430EUZ docking station.
According to the manufacturer's number UM.JE1EE.A04 and comparison with other suppliers (mainly from Ukraine), the specifications are correct. The pictures are therefore wrong with the connections. The power supply unit is integrated, so it is connected directly with a power cable.
Attached is one of these suppliers from Ukraine with the correct pictures of this model: https://fixer.com.ua/tft-monitors/acer-eb321hquawidp-um.je1ee.a04_835429.html
PS: I have forwarded this for verification.