Hi Bud
I would contact them by phone, make sure you ask their name when you phone them, if you are unsure of the spelling ask.
For PIP you need to contact PIP help line 0800 121 4433
For ESA you need to contact ESA Enquiry line: 0800 169 0310
Best time to phone is first thing in the morning as you usually will not have to wait too long, other times, it's pot luck.
Gary
Nothing on this board constitutes legal advice - always consult a professional about specific problems