Advertisement on my desktop

So I was playing games on my PC and when I came off the game I had an advertisement for HBO MAX as my desktop background. The only application I installed today was Novabench. After seeing the ad I uninstalled the programme and then also did 2 full scans for malware. I did one "Full Scan" and one "Microsoft Defender Antiviris (offline scan)".

I am using wallpaper engine but I've been using it for years and had no problems. I've been using that specific wall paper for a few days and hadn't seen anything. The application rules are set to pause the wallpaper also when running certain games.

All scans show no threats. So I'm unsure of what exactly happened. I hsve changed my wallpaper now in case that one had some advertisement in it as a prank or something but I hadn't seen anything like that for the past 4 days since I had changed it.

Any advice or thoughts? Or am I just overthinking this and it's just a weird bug?