I thought it would be worth sharing my experience with an error on the Google Store as I was unable to find any documentation online for such an error.

Having been offered a promotional deal on a Nest Hub, I followed the directions to place the order and received the following error:

An unexpected error has occurred. Please try again later. [OR_PTHA_02]

The solution was simple enough, but might not be immediately obvious. Especially considering the price is $0

Simply choosing the “Add payment method” and selecting a payment method you have stored is enough to get the checkout to complete.