****med and ghosted

Hi everyone, as a contractor who is still new in the industry unfortunately I made a mistake and Habitat Property Management is being slick because of it. A unit burnt in one of their properties and I did a labour and material quote, sent it through and two weeks later the property manager told me to collect material and fix the unit, i did all that. Now that im asking for payment HPM is now asking me to prove that I was assigned to do the works and yet the unit has been renovated, theyre now ghosting me. If anybody can assist me please do send me options? Im on WhatsApp *** and email is ***, thank you.