Check to see if you are still showing on the Insolvency Register.
If not your IVA has probably been failed but the other thing you have not stated is if creditors have been back in contact directly.
IVA started March 2011, Completed March 2016 and certificate issued 11 days after final payment. It was not always easy but then some of the best decisions aren't.
You need to check if the iVA is still running ( which I doubt, but it is possible). If so, speak to your IP and see if it can be salvaged. Otherwise you will be back to square one.
My opinions are merely that .. opinions based on experience. Always seek professional advice.
IVA Completed 23rd July 2013 .... C.C. 10th January 2014