I have an iPhone 14 Pro Max, and I have the same loss of connectivity problem with my Omnias that you describe with your Jabras. Resound Omnia 9 battery problem - #30 by jim_lewis
@david.hendon has also described the same problem with his Omnias. He also has the ReSound Ones and paradoxically has no connectivity problems with those using the same phone. GN Resound Omnia Bluetooth issues
You don’t have to repair a disconnected hearing aid. All you have to do is reboot the hearing aid. Hold down the button on the HA until it turns off; press the button to turn it on again. If using a disposable battery-powered HA (my Omnias), open and close the battery door.
To deal with wax accumulation in domes or molds, you might try buying a consumer-level Jodi Vac. https://www.amazon.com/Jodi-Consumer-Hearing-Vacuum-Cleaner/dp/B007ORQ01K/ A number of forum members, including me have bought them and are pretty satisfied with them as a cleaning tool.
Custom molds are easier to clean with the Jodi Vac than domes, in my experience. DON’T USE THE JODI VAC ON YOUR MICROPHONE OPENINGS. I did initially with my Quattros several years ago, and that may have helped kill the external mics on several Quattros.
Don’t know why some folks have the BT connection problem, and others don’t. I also have an Apple Watch Ultra and apps galore on my iPhone that want to share the BT connection, so that may have something to do with the connectivity loss if I go away from my iPhone for an extended period of time. I’ve also wondered if the Omnia running BT 5.3 and perhaps being set up (hopefully) to eventually do BT LE Audio has something to do with the less-than-stellar MFI connectivity maintenance. (Or maybe lack of Apple motivation to address HA bugs in iOS?!). As I’ve noted in previous posts, it’s not just loss of connectivity to the ReSound Smart 3D app. When connectivity is lost, it also shows up in Settings, Accessibility, Hearing Devices as loss of basic MFi connectivity.
Edit_Update (8/5/23): To fix the BT connectivity problem, it seems turning off BT for more than TWO MINUTES may work, rather than having to reboot the HA’s: GN Resound Omnia Bluetooth issues - #24 by jim_lewis