Peplink Max API cmd.sms.sendMessage "Unsupported Request" frimware up to date (8.3.0)

Hi,

My frimware is up to date (8.3.0) but when trying this command:

api/cmd.sms.sendMessage

I get:

{
“stat”: “fail”,
“code”: 404,
“message”: “Unsupported request”
}

All other APIs I’ve used work perfectly, it’s just this one and I really need to be able to use it.

Firmware 8.3.0 build 5229
Peplink MAX Transit Pro

Opening up an old thread here, but finding myself in the exact same situation with a MAX BR1 Mini HR1 on 8.3.0 build 5256 firmware (the latest). I downgraded to 8.2.1 build 5195 and cmd.sms.sendMessage works perfectly. Appears to be a problem with the latest version of the firmware.