We had issues with this at work. We're a healthcare facility that grew faster than our IT infrastructure or admin expertise did. A couple of years ago, we star

We had issues with this at work. We're a healthcare facility that grew faster than our IT infrastructure or admin expertise did. A couple of years ago, we started having issues with our wifi like you're describing. Connecting devices would work, but nothing new could join the network. The issue? DHCP lease times were set to 30 days in a facility where hundreds of transient devices per day could connect up to the wireless network. The IP pool unsurprisingly got exhausted. Our network engineer at the time was... not very good. It took two separate incidents with MDs complaining and me finally sniffing DHCP traffic on a spare laptop and emailing it to his boss to get it fixed.