@Bassi, Luca, Thanks for posting in Q&A. From your description, I know the AOVPN disconnect when sync from Intune. Based on my experience, I suspect that SyncML mismatched between Windows and Cloud CSP cache thus Intune will send a “replace” command during sync.
After researching, I find one similar case and it has extra space in the xml which cause the issue. You can firstly paste xml into notepad before we paste into Intune VPN configuration. Meanwhile, I also find there's known issue on windows 11 for AOVPN. Please update the devices to the latest to see if it works.
Please try the above suggestion and if there's any update, feel free to let us know.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.