Another 5 frequency channels of the module RAK811 for eu868

I try to use at+set_config=< ch_list >:,,,<dr_min>,<dr_max> to add channel frequency, use at+get_config=ch_list at cmd to check whether it is effective,
0,on,868100000,0,5;1,on,868300000,0,5;2,on,868500000,0,5;3,on,867100000,0,5;4,on,867300000,0,5;5,on,867500000,0,5;6,on,867700000,0,5;7,on,867900000,0,5;8,off;9,off;10,off;11,off;12,off;13,off;14,off;15,off,seem ok,but there are only three frequency in the gateway(868100000,868300000,868500000),How to make to after the check came for another 5 frequency channels?
Using this basic firmware:

Are those other frequencies even legally permitted in your location?

If you want to receive them, you may need to change the gateway configuration to receive them. For some of the more “complete product” RAK gateways that is done in the web configuration. For older kits and traditional gateways it is done in the global_conf.json file on the gateway’s filesystem.

You’ll need to take some time to understand how the receiver supports two tight groupings of four channels, around two more widely tunable IF’s.