I have recently been having issues with my WiFi connection (on both 2.4 GHz and 5 GHz networks) when my laptop is in clamshell mode and connected to an external 4k monitor. I use a USB-C to HDMI adapter (from Uni). From what I've read, it may be caused by interference created by my adapter (?) or something of the sort, and one solution I have tried to do is to wrap my adapter with aluminum foil (as suggested by some YouTube videos online). None of this appears to have any sort of effect. There are a few rare times I have successfully been able to maintain a connection, but the only thing that seems different in those situations are the position of the HDMI cable and adapter. I still don't have any idea as to what positions clearly allow for a connection, and those that do not.
I should note that I only have these connection issues when I solely use the external monitor. If I connect my device to the monitor, and use the laptop's built-in screen as well as the external monitor, the wifi works perfectly fine.
More information on my system:
Hardware: 2.2 GHz Intel Core i7, 16 GB 2400 MHz DDR4, Intel UHD Graphics 630 1536 MB, Radeon Pro 555X
How exactly should I resolve this issue?