Recently transplanted trees can be later starting than established trees, sometimes by several weeks or more, partly depending on how the tree was handled after digging and when it was planted. Check the tree by scraping the bark with a fingernail; see if the layer under the bark is green. If so, the top part of the tree is alive and waiting for more root development before "waking up".
In any case, if you believe there is a problem, contact your retailer for advice and/or warranty instructions.
If you lose a tree in a group or hedgerow planting, you can replant that spot the following year, being sure to keep the neighboring trees pruned so as not to shade out the smaller tree.
For information about planting fruit trees, see Planting Your Backyard Orchard.