How set tx-power for Senao 200mW

Hello i have problem iwth set t-power on MT 2.8.17 i have pcmcia Senao 200mW but now MT set default tx-power and default is about 100mW but I want set 200mW i try make:
interface wireless and them set 0 tx-power 23 ← set in dBi nad nothing
them i try interface wireless and them edit 0 tx-power and in text editor del default text and write 23 and make CTRL+O and make save and exit them still nothing and when i make edit agai nthem i have still write “default” but last time when i change this i make Save (CTRL+O) any can help me ?.

that should be fixed in 2.8.18