Pumping advice

Hi there! Looking for some advice on how to boost my milk supply.

So, I went back to work when my baby was 9 weeks old. For a long time I had major oversupply and my freezer was full. Well, probably about January my supply started to drop and I wasn’t able to make enough every day so we started to use my freezer supply. As of right now, I make about 10 oz a day and my freezer supply is gone so we have had to use formula. I have no problem using formula, but the issue really is cost. I’m not sure what happened to make my supply drop so low. I have kept a pretty consistent pumping schedule during the day (5-6 times), and then try to nurse at least once because I don’t want to be exclusively pumping. I’ve tried oatmeal, brewers yeast, mother’s milk tea, body armor, tons of water, power pumping, fennel oil, and I feel like nothing is working at all. He’s 8 months old now and I really want to keep going until he’s a year, but it’s just really disheartening. I’m willing to do almost anything to help. Thanks in advance!