Hi  @ATC23-IT-PH 

Maybe there are too many client devices are using 2.4Ghz, and the APs are too close to each other.

Try the following steps:

1. Upgrade the EAP firmware to the newest one;

2. Check SSID settings, make sure you have 5Ghz enabled, WPA mode choose WPA2-PSK/AES, and disable PMF, so this SSID can be compatible with more devices;

3. Set up Client Rate Limit for the SSID, specially the "Upload Limit". Some applications may occupy full upload bandwidth that will also slow down other devices. 

ATC23-IT-PH wrote
Need help in lowering the amount of Rx frames in our office network. All APs are using the standard config (all on "Auto) with both 2.4 and 5 Ghz Radios turned on. Network holds 55 to 60 Users with 2 ISP's holding the network. Am running out of ideas to limit the congestion as its affecting even the printers. Thanks