I have used this method to buy thousands call of duty mobile cp for free
A aged google play account [ atleast 2 year old ]
Different payment methods [ credit / debit card , UPI IDs , Google play recharge code ]
The Method :
So we are gonna use an aged google play account to buy some in app purchases stuff like coins and shit but we are gonna refund them without losing access to item in game !
keep in mind that the account you use for this must not have been used to refund any purchase in the past !
First of all create a new user profile on your phone [ if u dont know how to do it , google it ]
Go through set up process of new user [ some stock roms dont require this ]
connect to a vpn [ same country ] or if you are using mobile data just turn airplane mode on and off twice to get a new ip address assigned to your device
now set up new user and log in to google play
Install your game in which you want to buy in game currency , for example call of duty mobile
Now attach a payment method to the google account if not alreay done
Open your game / app and buy smallest pack of in game currency [ to test ] .
After you buy just wait for 10 minutes then open playstore and click on your account’s profile icon or open side menu [ on older versions of play store ] then open “help and feedback” section and there you will see an option called "Request a refund on Google play " , click on it then click on “next” then select yes > next , now select the purchase you just made and click next , now select reason as “i purchased this but didnt recieve it” and request a refund .
if the request gets approved then you can try buying a bigger pack of in game currency / item but not more than 10$ . Go beyond that and then game companies and google actually review refund requests and you may lose in game currency or maybe account will be banned [ happens on pubg ] . i have done this on cod mobile and i never lost any in game items ! Dont overdo this and remember that the maximum refund requests you can get approved on an aged accounts is 5 , after this they will reject them .