They delivered the load to my neighbor's yard by mistake.

Whoopsie!

Check with your neighbor first and make sure that they did not also have a ChipDrop request in place.  If it was in fact a mistake, please consider using the material from its current location.  It would certainly be appreciated!  Feel free to send the tree company an email letting them know about their mixup.  The feedback is important.

If you absolutely cannot use the material in it's current location (like if it's half a block down the street), then send us an email, and be sure to cc the tree company on it as well.  The tree company should be willing to help you out and fix their mistake.