JRAIN added this in another post and it's worked for me. You need to: After you finish, Windows works properly.  I'm using a Surface Pro (Win 10) with two Dell P2418HT's and all three work great! I have a Surface Dock 2 with both monitors using USB-C to HDMI cables to connect and cannot use DDM, so Windows was my only option.
Hello, Have a pair of P2418HT touch monitors each running to it's own graphics card via DP in a Windows 11 Pro custom system. Running DDM 2.0.0.135. If both P2418HT are connected, touch only works on one. If only a single P2418HT is connected, touch works fine. Is DDM not capable of simultaneously supporting two touch screen monitors? Thanks, Dale
P2418HT, two, touch only works on one at a time