If you are in a situation where a blocked number calls and says you are late on a bill payment and that you should pay to avoid it doubling, you should call the Federal Trade Commission.
The Federal Trade Commission (FTC) handles cases related to check and other scams and so you should call them if such a call is made to you.
Be aware that there is no bill payment that will double in 24 hours and that the usage of a blocked number is not allowed to debt collectors. So this is a scam and you should lodge a complaint with the FTC.
Find out more on the Federal Trade Commission at https://brainly.com/question/19622049?referrer=searchResults
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