Credit rating dispute

I cancelled my contract 2020 just before covid lockdowns began due to your sim card not working in my new device, I had a second sim card emailed to me also but didn't work and after many attempts with your team I cancelled my contract. I received my final bill and when I rang to query it, as I had charge I didn't agree with, your contact centre was closed due to covid and I was directed to LIVE chat online. I tried this Live Chat function many times to try to discuss this query before I would pay, I tried this over the course of a couple months and was on hold on live chat for so long that my session would ‘time out’ and other times it would just say live chat isn't available. I looked online at your community forum to see if maybe it was my computer too slow, but I saw you had many complaints about not being able to get in touch with ID mobile during the pandemic due to contact centre closed and live chat function not working. So I took screen shots to show you when you contacted me. I then moved house end of July 2020 and I couldn’t update my home address with yourselves as I was not being able to get in touch with a live person by phone of live chat.  I didn't receive any bills or communication from yourself of course because of moving house. The account was forgotten about after this, as I didn't receive bills and had no contact from you and with the pandemic there was so much going on it was forgotten without having any comms from you. I noticed a couple of weeks ago when looking at my credit report, that I had late payments marks on my credit file since October and then a default mark.  I used your live chat function to query and it worked this time, I was able to query, paid my bill and asked for your complaints team to call me to resolve the markings on my credit file as it was not my fault of the system issues. Your complaints team called me, we lost connection mid-discussion and I used live chat again to request another call back, that was 5 days ago and I still haven't had a call back. Since then, I have left another message via your live chat requesting complaints team to call me, but again haven't had any contact back to me. I raised the issue with Experian and Equifax. Experian was resolved and confirmed agreement with yourselves that the late e and default are being removed from my credit file but Equifax said you denied removing these from my credit file with them and that you requested I use this ID community forum to contact you to resolve directly as your complaints team is not contacting me via telephone to resolve my issue. Please can you help? Many thanks