Hi,
From the release note of SAM it says that "When upgrading to SAM 6.2.1, NPM must first be upgraded to version 11.5.2. Once NPM has been upgraded, you will receive a notification that SAM alerts have failed to migrate successfully. SAM will correctly convert these alerts once it has been upgraded to version 6.2.1." However,upon checking the "Compatibility of SolarWinds Orion Products for Installation and Upgrade" it stated that this version is supported from the NPM version of 11.5.x and didn't specify that 11.5.2 version.
This can be the results of incompatibility issue during upgrade if this new version is only supported the version 11.5.2 of NPM module. Some of the users/ implementers are only checking the Compatibility SolarWinds Orion Products since all of the Modules are in there.