I made payment arrangements but was unable to pay when I said. what are my options. I plan on paying them in full very soon.
When you got the loan you signed a loan agreement. Didn't you read it? Yes, they can repossess your car for failure to comply with the loan agreement. Your "plan" to pay soon is pretty much irrelevant.
DISCLAIMER: This is not specific legal advice and does not establish an attorney/client relationship.