My next step would be to remove the add-on, uuid and secret, restart OH, then add it back. But with the announcement of the new myopenHAB perhaps now is a good time to switch to this new service.
It requires a different add-on jar and config is slightly different (no more .persist file) but it largely works the same.
Since my.openhab is going away in January it is a good time to switch. And perhaps in switching your problem will be solved.