Dying Hydrangea tree
The hydrangea appears to be suffering from a severe case of transplant shock. Go here to learn about that:
And go here for a more exhaustive discussion:
If the hydrangea continues to decline, it will not recover. The vendor may have provided a guarantee that allows for its replacement. Now is a good time to discuss that possibility and make these photos part of the conversation.
In the meantime, consider whether too much water may have contributed to the plant's stress. In Minnesota, heavy rain has been common lately and the hydrangea isn't far from the down spout.