Edgars - Unprofessional Service

I have purchased items online in May 2020 using my Edgars account and finally received my order recently . There was 2 items that was not delivered due to stock not been available. When I purchased it online there was stock but when I received my delivery unfortunately these 2 items were not included. They have stated in delivery note that these 2 items will be credited in my account but since then nothing has happened they expect me to pay for the full delivery even though they have not delivered the balance of my order. I get messages to pay my account and statements will full amount allocated to be paid.This is so unprofessional. You can never get any replies via email and no one is available to talk to you on the phone. I will wait till they decide to respond to be before I pay my account.