Love the way everyone gets their knickers in a twist.
Merlin shortened them to requirements just put the levers on the wrong calipers. Suggest you call them and ask about getting them swapped over by Merlin. Sounds like an honest mistake.
You don’t need olives etc. because they are the right length.
Bleeding Shimano’s is pretty easy to be honest so its a good job to do yourself if you have the little yellow bucket thingy.
So pleased I don’t work with the British bike buying public. You are all so full of pooh and happy to hang a bike shop / mechanic / trail maker or anyone else you come across.
Mistakes and accidents happen – ask nicely and these things are usually remedied. No need to be mean and horrible.