Can I request alternative form of assessment?

I applied for PIP in November.

I have today recieved a letter stating I 'need' to attend a face to face consultation appointment.

I am currently going through it and have postpartum depression along with depression and anxiety. I haven't left my house in about 2 weeks. I cannot face anyone. I am so overwhelmed with dread and anxiety about this.

Is there a reason they give some people phone calls and some face to face?

Also can I request a phone call/home visit/video call?