i just realized i made my buttercream with salted butter. you can totally taste it. is there a fix for this???? i've already tried adding more powdered sugar but it's not working

I don't get the panic...Did you add salt to the buttercream, in addition to what is in the butter? Did you add more Vanilla Extract?

Is it super salty? If not, make another batch using unsalted butter and no additional salt and mix the 2 together.

I prefer to use salted butter in my buttercream. I don't add extra salt, though....what flavor cake is the buttercream being paired with? Maybe adding a coordinating extract will help to cut the saltiness....if not, the above idea from cupadeecakes is what I'd do.