Motorola T80 same model but different frekuency

hi all

can I ask for advice, I have some WT Motorola T80 Extreme, but in some WT the frequency channel shows numbers 1 to 20, while others show channel numbers 1 to 8, so these two WTs can’t transmit, how do I set the WT to channel 1 up to 8 can be changed to channels 1 to 20

maybe someone has had the same experience