My original S50 had the same problem--I could not get it to connect to any of the devices I owned. I am not normally an Apple user, but I bought an iPad (gen 9, 2021 model, WiFi only) just because most of the posts I have read from people successfully using the S50 had Apple equipment. But, no luck with that, either. I even tried monitoring the WiFi bands with a sniffer app on my phone to see if the S50's network connection ever appeared. It never did.
I opened a case with ZWO support, and they eventually agreed to replace my original S50 with a new one. The turn-around time from opening the support ticket to receiving the replacement was about two months. The new unit works much better than the old one did. Interestingly, the new S50 also does not work well with the iPad, but it works great with my Android phone.
So, if your S50 is still in warranty, you might want to try to get it replaced. It seems to me that some of them have a defective WiFi board.