This is a re-post since it it was created in the wrong forum first.
I have to cast Prayer to get the proper 102 Stamina buff, counter to what the tooltip says.
I’ve got the same issue and looking into it I see this discussion came up years ago, but no post that mentions any solution - at least not that I can find. Very annoying
Ah ok, I just checked and if you look on your character page with all your stats and gear, take off the buff, rebuff and you can see that it shows that it does give the proper buff to 102 but for some reason the buff note on top of screen says it’s given you +79 stam. Weird. - - and still very annoying!
I don’t think this is true since in BGs I buff without mats and it gives more Stam if I re-buff with Prayer.