We just started receiving these after months of using Samanage without issue. This resolved the issue after about an hour.
Login to the O365 portal>Admin Centers>Security & Compliance>Threat Management>Safe Links>Policies that apply to specific recipients>edit default policy or create a new one>Settings>Do not rewrite the following URLs>add *samanage.com* and *mailer.samanage.com* >save it and wait for 30-60 minutes and test a new ticket.
The confusion for me was I was trying to use an existing email. The policy only applies to new emails from Samanage. I created a new ticket to verify the links, specifically "View Details" were not being rewritten.
The rewritten URL takes you to the nam03.safelinks.protection.outlook domain vs mailer.samanage.com.