Loose hammer-in rise & fall gutter brackets

[LesCM19]

A few of theses have come loose in the middle of a long section, I could probably withdraw them out of the wall if I tried and they move in the wind.
What is the proceedure, remove some of the loose ones so gutter is still supported, drill out, fill with mortar, push back in? Will I be able to push enough mortar down the hole with a normal pointing trowel?

 

[catlad]

You could try everbuild anchorset one is red and one is green ie. fast set slow set resin.

 

[Mw Roofline]

Locate to undisturbed mortar, drill 3x 6mm holes and then hammer the bugger in. Won't move for shyte.