Magicspam extension missing in Extension catalog but installed

I have the Magicspam extension installed and work, but since some days this extension is missing under the extensions

On one server with Onyx 17.8.11 Update #13 the extension is installed and works, but I do not see it anymore under: Plesk Panel > Extensions > My Extensions
also I cant find it within the extension search and even not under plesk panel > Extensions > Extensions Catalog > Categories.

# plesk bin extension -l does not show magicspam in the listing

On another Server with...

Magicspam extension missing in Extension catalog but installed