If you are looking for a refund you should call into the company as the best option is to talk with a representative about the charges. If it is fraud you should call in to cancel your card and request a refund.
The issue and preferred resolution, in GetHuman-kimgalla's own words:
The problem I ran into: There are charges from Roblox charged by Google play, that I did not authorize
I trust that Google Play will make this right and come up with a resolution that is fair.
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