I have never had any luck troubleshooting bugs with Apple engineers. Many of these bugs have persisted 5+ years and I have no hope they’re going to try to fix them. This one, however, is an ecosystem breaking bug. If they don’t fix this, there is less barrier to jump to Android since the messages wouldn’t go to a new phone.First, I want to say thanks to the OP.
I am running into this exact same issue and it occurred after I factory reset my phone and updated to 13.6. I noticed the icloud/imessage issue around mid July and spent days trying different things. I finally stumbled upon your post about 5 days ago.
I've been in regular contact with Apple for about 2-2.5 weeks, sent log files, remote screen shared, provided image uploads, etc. Their answer to me was to create a new secondary Apple ID, that was essentially their final solution. I told them I don't accept that as an answer and do not want to manage a second ID and that it has worked fine for years. The engineer I've been working with simply stated "we appear to have reached the end of our troubleshooting path". I doubt I'll hear anything back from the engineer.
I also attempted to update to the latest version of iOS 14 public beta - problem still exists there.
One addtional observation, if you have a Mac and it's also using iMessages in the cloud, it appears to sync. However, attempting to go into preferences and unchecking imessages in the cloud, and selecting disable all devices returns the exact same error message that's present on iPhone.
My engineer claims to have never heard of this issue before (seems like they always say that), but based on this post it's fairly widespread and likely others have it but don't know it or won't know it until they reset their device is my guess. For those of you having the issue, I'd recommend filing a bug report for sure.
I have never had any luck troubleshooting bugs with Apple engineers. Many of these bugs have persisted 5+ years and I have no hope they’re going to try to fix them. This one, however, is an ecosystem breaking bug. If they don’t fix this, there is less barrier to jump to Android since the messages wouldn’t go to a new phone.
Many of you have stated that this problem stems from the apple ecosystem. But it's different to me. because i only have one apple device. There is only one iphone and apple watch. And the problem continues resolutely. I will wait for the 30 days that continue after the beginning of the problem. I will contact apple again for my lost message data. if apple still can't find a solution... suing is also an option. maybe this could be a very good cause of compensation
Any idea when your 30 day clock started counting down from? I reset my iPhone the day iOS 13.6 was released, and I seem to recall (but am not certain) that it was released on 7/14. Assuming that is correct, my 30 day clock should count down to zero on August 13 - though I'd wait until August 15 to be safe. In my conversations with the engineers, they said it was unrelated to any 30 day counter as the request to delete messages and start the 30 day countdown was not submitted due to the error about being unable to change iCloud settings. They further proved that to me as there should have been an option to re-enable messages within those 30 days and that option was never presented. So at least in my case and from my conversation, the 30 day clock to delete never started - tho I will be checking Aug 15.
Joy. Thankfully I have on site backups.As an update, I heard back from an engineer about an hour ago. He said the issue is far more widespread and reports continue to come in. The engineers don't have a set date for resolution and that it likely will not be resolved in the next few days. It has nothing to do with iOS version (beta or otherwise) it has to do with a key/decryption issue which presents itself after a factory reset of the device has occurred. I'm not sure of the accuracy behind that but it seems to make sense.
What doesn't make sense is why the Apple System Status page shows services are normal...
I only have an apple device and this has icloud message sync issue for five days. All Apple services seem to work but I think there is a problem with apple side.