Directions rose red over midnight blue

Try a strand test. I'd suspect if it's more on the teal green side, it's just going to go brown/mud on the teal parts, and very dark, if not near black, pinkish brown on the brown parts. Having said that, Rose Red is really highly pigmented, so I could be wrong. If the teal is more on the blue side (hard to imagine that as it's gone over ginger) then it might pull more dark purple.

Difficult to say without seeing a photo of the current hair though.

It's more green. Doesn't really show in photos that we'll.  Picked up some rose red today so will try strand test.

Yeah, that looks really dark. I don't think it'll do much other than be brown with maaaaaybe a purple tinge. Not sure.

I like how it looks though! I'd keep that 🙂

I would wash it with dandruff shampoo and let it sit for half an hour before rinsing if you want a purple. Adding more colour now will just make it look black. I also really like the dark green/black you have now.

In the photos it looks really nice but in real life there is brown and greyish parts. I have a little midnight blue left. Would it be worth trying to put it on again?

No. Blue doesn't go well over ginger, so it's just not worth it. You would be much better fading at least some of the blue as wicked pixie says, then putting the rose red over. Rose red covers ginger well.

I don't have anti dandruff shampoo but I do have coal tar shampoo for my psoriasis. Never used it when had directions in hair but it has stripped box dyes so it should work to fade out the blue

Yeah. It'll do the same. Even more effectively to be honest!

Update

Photo isn't catching well but colour has turned out a dark brown with dark pink/purple tones.