My lo is over 6 months old and has been breastfed since birth.
Just to check, what kind of pump are you using?
Are you on any hormonal birth control?
When you say cereal and vegetables, does that mean two meals a day? That would be a fair bit for a baby just over six months old. That amount could be filling her up and causing her to nurse less, and thus your supply could drop from that.
Another tip for working and pumping is to get her carers to feed her any solids while you are at work, and just nurse with no solids while you are at home. That will give your breasts more natural stimulation from direct nursing.
Please get back w/ answers to pps' questions.
Unfortunately, the Playtex pumps are generally not among our recommended pumps, as they don't seem to hold up / work as well (and can even cause tissue damage in some women).
I don't know if maintenance will work or not, but it certainly wouldn't hurt to try.