I just switched my SIM card between my Google Pixel and my Note 8. I have done this successfully today a couple of times, and each time my Message + messages re-synced between devices.

Now, on either device, I tap on "restore messages" and I get a quick appearing bubble that tells me to subscribe to integrated messaging in order to restore messages. I go to settings and tap on Activate account, it says  "Please Wait, Starting Services", and then I'm back to square one. I cannot restore my messages. My Windows 10 tablet app has all of my texts from each device in the correct order, so that's working, but the two devices themselves wont restore messages.

I've deleted the cache, uninstalled updates, I cannot uninstall the app since I'm on a Samsung, and I'm not allowed to decided what I do and do not want installed on the phone I paid $1,000 for, so the best I could do is disable and then re-enable. And the problem still exists.

So, how to I subscribe to a service that I never un-subscribed from?