U2720Q, no HDMI signal from your device

Update: I noticed that my monitor will only and exclusively accept signal from a specific device now after using that device. That specific device (OSSC), is able to output multiple resolutions, which the monitor accepts. One of the resolutions is 1280x960. Despite setting the output of that device to 1920x1080, which my monitor properly accepts, other devices are still not recognized anymore for some reasons. 

I will continue investigating and hopefully will have some more news from Dell Team,

Thanks!

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Just so you know, the HDMI signal is not coming from a computer. It's coming from gaming consoles and the OSSC (OpenSource Scan Converter)

I will try those steps and will report back, appreciate the help!

I have talked to 3-4 people already in the Dell Support chat. Everyone starting the discussion all over again every time, asking me to share personal information with them. I spent 2 hours with someone for another person to come in and ask me the same things all over again. Is this a joke?

* Turn the PC and U2720Q off
* Disconnect every cable from the U2720Q (including the power cable)
* Disconnect the other end of the HDMI cable from the PC
* Press and hold the U2720Q power button for 8 seconds
* Reconnect the power cable and HDMI cable to the U2720Q
* Reconnect the other end of the HDMI cable to the PC
* Turn the U2720Q on, then the PC. What happens?

So, I just tried these steps again, same issue persists -> "No HDMI signal from your device" while the same HDMI cable and the same device work perfectly on another display.

The display is not broken.

HDMI signal is getting detected by one specific device and USB-C signal works perfectly.

Sounds like the display broke. It happens.

FYI, Dell Support has not been helpful at all, the Dell Support Chat is chaotic and clearly these people are 100% clueless about the Dell products.

They ended up telling me that my devices are at fault (?), while they work perfectly on other displays. On top of repeating myself 3 times to different people, I did not get any help in the end and it seems like nobody wants to help me because they have no idea what is going on and don't feel like getting this problem resolved. It would be in their best interest to do so, assuming the same problem occurs on the same or other monitors.

Very disappointed, as always, from Dell Support.