Update from Electroverse and Octopus:
It's now 10 days since I found out that the option to pay Electroverse from my Octopus Energy account had been removed without my knowledge
10 days since I complained to Octopus, who said it was nothing to do with them and I should talk to Electroverse (which is an Octopus company)
10 days since I complained to Electroverse (who I then discovered don't provide support over weekends)
10 days since I set up the payment method again in the Electroverse app (and it started to show as "Pending")
7 days since Electroverse replied to my complaint without attempting to understand the issue
7 days since I repeated the complaint to Electroverse (payment method still "Pending" in the app)
5 days since Electroverse replied saying the payment method had been removed on November 13th, and blamed it on a system error, but didn't say how it was going to be put right
4 days since Electroverse support passed the payment method "Pending" issue to their "tech people"
3 days since Electroverse blamed it on an issue over the weekend "that caused some disruption in the app" (ignoring the fact that all the problems I encountered had started before the weekend)
3 days since Electroverse support asked me to add the payment method again (despite the fact that I had already done so, it was still showing "Pending", after a week, I had told them this already, and the app wouldn't let me remove it, edit it, or do it again)
3 days since I pointed this out again to Electroverse (who of course don't provide support over weekends)
This afternoon Electroverse replied to say their system shows my Octopus Energy account has a "Loss Pending" status, so the app will continue to show the payment method as "Pending", and I should talk to Octopus!
To summarise, I first complained to Octopus, they bounced me over to Electroverse who messed me around for over a week, gave me two bogus excuses for what had happened, then finally looked into the issue properly, decided they don't think its their fault and bounced me back to Octopus.
I have been with Octopus Energy for years, always maintaining a steady monthly direct debit to build up credit every summer. My credit balance is enough to pay for all the home energy and Electroverse charging I could possibly use for several months. There is no way there should be a "Loss Pending" status against my account.
So I phoned Octopus, who asked me to email all the details to them.
The email has gone off to Octopus. It ends with the line "Please fix this issue asap if you want to keep me as a customer". Let's see if they do.