Billed for cell phone insurance

I purchased a cellular telephone from Edgars, The Grove, back in 2012. I recall being asked whether I would like to take out insurance on the phone. I declined the offer as my husband works for a short term insurance company and we have already got cover. I do not recall signing an agreement for cell phone insurance. Since 2012, I have received my statements in fits and starts and only in the past 6months or so have I received electronic statements and it was at this stage that I noticed cell phone insurance charges. After inquiring about this, I was informed by Edgars that the store where I purchased the phone will contact me, which they did, only to inform me that they are busy with a store move and need to find the relevant documentation. I was promised feedback for Monday 7 March 2016. Needless to say to date I have not had any feedback and the mails I have sent to Edgars have not been responded to. All I want is to see where I signed for cell phone insurance.