Telephone call re Interview out of the blue

As background I filled in an esa 50 form back in Dec 2019 for reassessment. (I am in the support group) but due to COVID I was never approached for an interview. I assume my award was automatically renewed. I simply never heard from them and was afraid to contact them.
I received a phone call today from the DWP which my husband took. I have Chronic Fatigue and Autism and find the whole benefits process extremely stressful. My husband acts as my carer for such things. It was a short call but the lady seems to be asking to conduct a telephone assessment.
There has been no warning and I haven't filled in a form since 2019. I'm in a state of panic as she wants to phone back, I think tomorrow to arrange to call in the afternoon and I have no idea what for. Is it for an assessment and do I have the right to time to prepare?
It has completely thrown me as I don't do well with having things sprung on me and I don't know how to respond or get my husband to respond when the lady phones back. I'm afraid that if I tell her I need more time that I will breach some rule and disqualify myself.
I could really do with some advice regarding what to expect. What I have a right to and basically how to handle things.
Many thanks