Just joined...just leaving

Switched over from ID mobile about 1 week ago and since then have no connection at all.  I can connect to Wifi and make wifi calls, but when out and about the Sim shows no connection and and excalamation over my Pixel 9 Signal status.  Obviously I've checked my APN details against those supplied, restarted, ejected and reinserted SIM...nothing.

It appears that Smarty mobile just want to take the money for a month, then you leave.  Anyone from Smarty wish to address this issue before I siwth to another provider?  Customer chat doesn't work and online support is minimal.