I shall advice you:
Don't use the wrong device — Using it could complicate your claim, as it might be interpreted as acceptance.
Contact Microsoft Support immediately — Call or chat via support.microsoft.com. Reference your original service order/case number and clearly state:
You submitted a Surface Pro (tablet)
You received a Surface Laptop 13" instead
This is a fulfillment error, and you want your correct device returned.
Take photos of the box, the device you received, the shipping label, and any paperwork inside. Note the serial number of the device you received.
You can also reach out via the Microsoft Surface X account (@Surface)