Can I change the integrated AP from AX to b/g/n to support an old device?

My Max’s AP settings say its Protocol is [Max AP protocols]configured for 802.11n/ax . And just below it says my integrated AP supports 8xxx n/ac only (not ax) I would like to switch that back to B/G/N for a bit to see if I can get an older device to connect. (troubleshooting why I cannot seem to connect) I thought that would be somewhere, but its eluding my. Manual online doesn’t show where that might be.

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