Zelle or Venmo
Zelle and Venmo send money to a personal handle. They are a poor way to start a car shipment. Pay a company named in a written contract, after you have checked that company's authority yourself.
Zelle and Venmo move money between people. A car shipment is a contract with a business. Those two facts do not fit together at the start of a job. A personal handle has no bill of lading, no easy card dispute, and no obvious tie to the legal name on a USDOT record.
What the pattern looks like
The message offers a very low price, asks you to send a deposit to a first name, and stalls when you ask for the MC number. Treat that combination as a stop. Do not send a small test payment to see what happens.
What to do instead
Pay the business named in the contract, by a method that contract lists, after the docket checks out. If a real carrier's contract truly names a business account on one of these apps, the legal name should still match the federal record, and you should still get a receipt. RideShipper does not ask you to pay a personal handle, and it does not take payment for the freight.