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Hello, i recently buy BE550 Router and i notice when i select OFDMA + MU-MIMO on WIFI settings, after refresh or after little time router alone switch to: OFDMA only. And after switching it i need res

Just got the BE550 and I dont know if been dumb but in the wifi settings it will allow me to change the OFDMA and MU MIMO but i press save it glitches out and disconnects all devices and returns ack t