u/Desperate-Map-5822

Under england. I am currently working really late shift patterns and not able to get out to the pharmacy in time so my sister in law went for me. I didnt know this until now but because I claim PIP she thought that meant I was exempt from paying and had them tick that at the pharmacy for me, but now Ive had a penalty letter in the post asking me to pay £100 ontop of my fees.

I had asked her what I owed her for getting it and she kept saying it was fine on her and I just assumed she was trying to be nice

How do I go about telling them that they are mistaken and I will not be paying this? I do not have money to throw away on this penalty