Sonshine Motors Repossession after being told I was paid up. Fort Walton Beach Florida

I have been a customer with Son Shine Motors since September of 2013. I put a $1200 down payment and they were great people there and treated us very nicely. In December I paid my payment in advanced all the way until February. Then in February I paid until April. I then called April 1st 2014 and made sure I did not have a payment for March. The lady I spoke to clearly told me I did not have a payment for March and I was paid up until April 5th 2014 Which is a Saturday. Monday April 7th, the repossessed my truck. I called and asked why and they told me I was 2 months past due. I told them that I called and all and they said there was nothing they could do. I have been a loyal cuatomer and even referred a paying customer to them who bought a vehicle from them. She said I was still technically past due by 1 business day and I was a big girl and should know when my payment is due. I absolutely agree, but when I call to double check like an adult and an employee there specifically tells me I do not have a payment i feel like they are at fault