Closing Edgars Account has turned into nightmare

Having closed my Edgars account in August 2020 with it being fully paid up, for the past two months I have been receiving non-stop correspondence via e-mail and SMS from Edgars/RCS regarding owing money. I do not understand why that is the case as I settled everything with Edgars and received confirmation that my account was closed. When I try to call Edgars/RCS, either I am not listened to and transferred forever or I am put on hold until the line cuts. That also happened when I visited an Edgars store and called in-store.