Gap where brick meets flashing - Recommendations?

Hi all! For a while now, I've been hearing what sounds like mud daubers or wasps, seemingly behind my wall in my upstairs media room. I think I finally found the cause - there's a huge mud dauber/wasp nest right on the other side of the wall under the eave. That said, while I was snapping photos of this, I noticed what appears to be, a significant amount of mortar that has chipped away or is missing entirely where the flashing meets the brick. This is a new construction house, just outside of warranty, 11 month inspector did not catch.

What's your guys recommendation/suggestions on repair? Mortar and then paint? Some form of caulking?

Edit: I guess in theory, with that big of a gap, I could actually have mud daubers between my brick and the sheathing so could be 2 birds with one stone here.

Thanks all!