Please should I call the bailiff or email TfL

Hi, Please can you help me.on 14/01/2016 tfl issued a pcn via camera because I parked in double red route. i made a appeal but lost on the 03/05/2016 I paid the full charge on the 19/05/2016 today I received notice of enforcement asking me to pay £278. i checked tfl website and find out that on the 19/05/2016 at 10:23 paid then on the 19/05/2016 10:27 refund requested they had some problem with their payment service but I don’t know about all this and 4 month later I moved from my address I found out about everything just today. What should I do.