Frustrated

My baby girl wasn’t seeming to get enough when I breastfed, so we’ve been giving her formula and I’ve been trying to pump as often as I can. It seems like no matter how much I pump I get less than an ounce a day. When I started I could get closer to 4-5 oz per day. I’ve tried everything apart from the lactation supplements to get milk going. I know “fed is best” and it really doesn’t matter if I breastfeed or not but I want that connection with my daughter. What do I do??