Chan_dongle with RasPBX (Asterisk + FreePBX) errors

Hi guys

I’m trying to use a Huawei K3520 with RasPBX and can’t get to send SMS’s with it?

The output of dongle sms dongle0 <phone#> test is:

[dongle0] SMS queued for send with id 0xb3b111e0

[2021-01-14 10:30:56] ERROR[25027]: at_response.c:500 at_response_error: [dongle0] Error sending SMS message 0xb3b111e0

Any idea what’s wrong with it?

Thanks