The legendary ships have to be purchased in limited edition packs which are not available constantly.
They are available at the discression of the people who run the game.
The 'Monarch' is one of the skins for the Galaxy class.
If you mean the 'Verity-class Legendary Command Dreadnought Cruiser', and you have purchased either of the 10 year anniversary packs, then yes, you should have access to that ship (and the Monarch skin for the Galaxy class as well).
If you have the pack, and can claim the other ships in the pack but not this one then you have either run out of slots, already have it equipped (possibly in Dry Dock if you cannnot see it in your ship list) or have encountered a bug of some kind.
Comments
They are available at the discression of the people who run the game.
If you mean the 'Verity-class Legendary Command Dreadnought Cruiser', and you have purchased either of the 10 year anniversary packs, then yes, you should have access to that ship (and the Monarch skin for the Galaxy class as well).
If you have the pack, and can claim the other ships in the pack but not this one then you have either run out of slots, already have it equipped (possibly in Dry Dock if you cannnot see it in your ship list) or have encountered a bug of some kind.