Debitted 16400 rupees without giving a product

Sir,  I am a retited person aged 75 years. I buyed a smart health watch for which i requared a barcode scanner.free. I was searching in google play i got it and did my job. During search i just clicked their icon  but when i saw it was chargable I closed it. i never used their product but they debitted rupees 16400 for nothingfrom my google account.Pl get my money back. I am a poor man I can not afford to buy their product nor I used it