Slow Internet on Wifi

[Elisup]

Hi Team,

We have new building, Fortigate 400E and FortiAPs, the speed of the internet is crawling on wifi and it's normal on the hard wired, If I connect the APs on the cloud the speed is perfect, it's new device with no users yet but that's weird, I have a ticket open with the support and that's how we tested using the cloud, we tested with bridge and tunnel ssid and it's the same issue, they suspect something with the tcp mss, I did show full on the interfaces and it's the same, any suggestions?