Well, technically you will get an account limitation first inquiring why you are processing so many returns. They will need you to submit a plan of action on you will address this matter. Failure to give them a path on you will accomplish this task, they will then suspend you indefinitely.
Any abnormal circumstances can get your account in trouble. That can be disputes, suspicious transactions and yes it can also include too many refunds.
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AGED SUPER HIGH LIMIT ACCOUNTS: 10,000/$1,000,000 and 25,000/$500,000