you need to speak to Yan i think it was in MZD technical Germany.
He or they actually know all there is to know IME, when Mazda CS put me through to them chap i spoke too once i told him the very long saga with my phone not connecting reliably immediatly said it wasn't the phone at fault but the module. I even got a case number.
Still Mazda CS insisted on yet another software update which made things worst, in that it dropped the connection even more (511), along with more testing.
It reached the stage where i bluntly told them that after 25 years working in maintenance if i hadn't changed a part by now then questions about my competence would be asked.
Since the module was replaced which is for BT and wi-fi etc, my phone has connected everytime.
You need to start getting a little more assertive perhaps?