1) Buy the in-app purchase you want

2) Go play.google.com and click the gear icon on the top right corner and click "My account"

3) Find the purchase you made under the order history and click the 3 dots on the right and click report a problem

4) Select "I purchased this but did not receive it"

5) Type When I tried to buy it, the app force closed and the stuff I want is not received "

6) They will refund you immediately if the purchase is less than $10 and if it is more than $50, it will take a few days.