Payday loans companies are forbidden from doing business in the state of Virginia unless licensed in the state of Virginia. If they are unlicensed, they cannot collect from you, and it is in fact a felony to do so. A quick check of the licensing shows that no firm doing business as CashNetUSA is licensed in the state of Virginia.
In addition, there are several legal formalities which must be followed. Under Virginia Code 6.2-1816, payday loans must have a written agreement signed by both parties, and they must have evidence of receipt of a check from you as security for the loan. I'm willing to bet they haven't followed these formalities.
It would be prudent to discontinue any direct withdrawal immediately, and move all of your money to another bank account. If they contact you, you should advise them that you require proof that they are licensed to do business in the state of Virginia, and that they are subject to the Fair Debt Collection Practices Act (which applies even if they are the original lender).
You may benefit from the assistance of an attorney in this matter, but it is likely to be a waste of money. Odds are they know the law, and are simply attempting to prey on your ignorance. If they are foolish enough to take direct legal action against you, however, then it may be advisable to retain an attorney to counter-sue for violation of the FDCPA and the Virginia Payday Loan statutes.
This response is not offered as legal advice, but is only a general informational response for public interest. No one reading this is authorized to claim that an attorney client relationship exists with this writer or the writer's law firm.