CB ESA (support) but contacted by compliance team

I’ve been in the support group of CB ESA since 2011. Last week I received a letter asking for my phone number as they needed more information from me. I phoned them but the officer was due on another call and wouldn’t tell me what information they want or why they would want to speak to me. He said he’d look at my file and if he needed to talk to me he’d send an appointment in the post so that we could have a longer telephone chat.
My mind is in overdrive now in trying to think what it could be. Have I unwittingly done something wrong? I know I’m allowed to have savings, so it can’t be that. And I did some voluntary work a few years ago, but I’m allowed to do that too, right? The only things that have changed in the last 5 years is that my husband now receives a state pension — does that change my CB ESA entitlement, should I have told them? Also, my son who receives PIP went away to Uni last year, but we notified the correct office about that.
Please can someone share some insight here because I feel really frightened that I might be under suspicion for something I don’t even know I’ve done.
Many thanks.

Thanks Gordon. My husband has state pension a private pension and an occupational pension. Do they affect my entitlement to CB-ESA, or is it just my own occupational pensions that are assessed? It’s all terribly confusing. Thanks for your guidance.

I just wanted to reassure anyone who reads this thread that the compliance team confirmed that the DWP had made an error.
It was very alarming to be contacted by them because it makes you think you must have done something wrong. But not always …. The officer was very nice and apologised for their error.