Charge against property

[tc70]

Hi, my civil partner died Feb 2013 leaving no will. The mortgage is still in her name. I have just applied and been accepted for a new mortgage as I cannot take over hers. My solicitor has started the searches and I didn't realise she had a loan (taken out with a previous partner) that has come up as a charge to the property. The charge is dated December 2006. I knew of the loan with Black Horse but not the attachment to the property, My solicitor had previously written to Marlin Europe who have since bought the debt from Black Horse informing them of no equity in the property at time of her death and her death certificate was also sent. Can they still apply this charge as I have carried on paying and overpaying mortgage? The money paid in that now has the house in positive equity is my hard earned cash. Any advice??