Lost of video signal with external monitor via USB-C

I bought the monitor Lenovo Q24h-10 and it was working properly for 6 days, even charging my macbook air 2020 - problem reported by other users-. The problem is that suddenly I lost the video signal on the external monitor. After some checks I see that connecting using an adaptor to HDMI it works, only when I connect directly with USB-C cable, it doesn´t work,

can it be a problem of the monitor? or is there anything I can check on my mac??

Thanks in advance for your support.