They have a link to a video that walks you through getting to an old order and adding those labs. I haven’t tried it but I think you have to add the entire list from that old order, then remove any you do not want. I keep asking them to create a section where your most ordered items (favorites) are grouped together so you can quickly pick and choose.
Another area they need to improve on is once the purchase is complete having to enter all your personal information (name, address, etc) over and over again for the lab form. It’s painful when you are buying several sets of duplicate labs on the same day.
@DonLigero