HSM not sending txt messages

So I believe the HSM has the ability to send alerts via txt when events happen when the system is armed. I think I have it setup properly inside the HSM app settings yet when I test it, I receive no txt. Does the number format have to have a + symbol before the number or does there have to be any special symbold in the number ?

Yes it has to be in E.164 format. So if you are in USA, +15554441234 as example, notice no spaces or dashes.

Just FYI, you can only use the native SMS messaging in Hubitat currently if you are in the USA (and Canada I believe but I'm not 100% sure) and it is limited to 10 texts a day.