female goldfinch is trying to get into the house

Question
A Small bird, possibly a female goldfinch, is trying to enter our home by banging on the windows. If this is someone`s pet, how do we go about catching it without stressing the bird.

Answer
I'm sorry I never got to your question. For some reason I never got notified of it.
Birds often mistake windows for open space they can fly into. When it's bright out, windows act like mirrors and reflect whatever is in front of it. This can be easily fixed by sticking something to the windows. There are stores that sell special UV stickers that practically invisible to the human eye but stand out like neon signs to birds. This will stop the bird from hitting window.