Trackpad not really usable after plugging in External Monitor

I just purchased an 2025 Macbook Air with an M4 chip. I have been loving it until yesterday when I tried to plug in my external monitor (LG 29UM55d) directly into the usb port using a new usb to HDMI Cable (6ft, 4K High Speed Thunderbolt 3/4 compatible). One that was done, my touchpad became unusable. When I try to use the pad the pointer jumps all over the screen and rarely accepts any clicks. I checked the refresh rate and it is set to 60. What else can I try?