A few options, firstly call it in on 150 (VM Phone - free) or 0345 454 1111 (any other phone - national rate). Use option 2 (faults), dont press any other buttons when offered and you should be in the queue for the next agent. Calling at 08.00 midweek (09.00 Sun) is the best time to get through quickly.
If you get cut off after an automated reboot cycle, just call back in a couple of minutes as the system should know that you have just been on and it hasn’t helped and put you in the queue.
Or.. try options 1,1,4,4, “thinking of leaving” - they usually pick those calls up in the UK (at 08.00) quickly and then transfer you to the appropriate queue (or cut you off !).
You can text VM on 0753 305 1809 include account name/number and what the issue is, there is also a “Chat” option on their website - but note that replies usually take longer as you have discovered.
Or you can speak to the team on WhatsApp by logging into your online account via a mobile handset and there will be a link to speak to VM by Whats App again... long waits if there are no agents
You could also try the freephone number 0800 052 0422 to discuss your account and see if that gets you there
Finally… A VM person should pick this up here and respond, but it can take a few days for them to get here.
I do not work for VM. My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired, 1 WiFi, 1 on PA) Hub5 in modem mode with Apple Airport Extreme Router +2 Airport Express's. On 250Mbps, Talk Anytime Phone, x2 Mobile SIM only iPhones.