Breastfeeding advice please

Jessica
So my son is now 5 months old and I've been working more now than ever (I hate it but I have to). Anyways I've noticed I'm pumping less and less and he seems to be getting more and more supplement. I hate it and want him to be breastfeed until a year. My question is how do I reverse this cycle. I feel like he gets more supplement than breast milk.