PIP letter lost.

Hi, I am new here so sorry if this has been answered I couldn't find similar to me that has been answered recently.
I'm 24 I've been on pIP since it was introduced. 
I have
- adhesions
- chronic spontaneous urticaria/angiodema with known triggers to be heat, cold, water, stress, anxiety and tight clothes
- gastritis
-reflux
- unknown malabsorptions
- bile salt malabsorption
- intestinal damage
-ibs
-anxiety
-agoraphobia
- hayfever/eczema/asthma severe
- possible endometriosis - will never be diagnosed as they have to apparently cut in to see which would leave worse adhesions etc.
I have a carer paid for by social services. She helps me
- prepare food and eat
- sort my medications
-make sure I'm clean
- helps me pay bills
- has to be outside with me for a few reasons. I could collapse, have allergies, if I am severely anxious I can be abusive and she helps stop retaliation,
- takes me to my hospital appointments ( 3 a week until January) 
- helps me manage my bowel issues
Basically everything in my care plan pretty much had a section for each PIP section. I sent my forms off the day I got them as I'd all prepared all my evidence 4 weeks ago. I have now been told theyre lost. So I resent them cost me around £8 but they are there, tracked signed and before 1pm. PIP have told me over the phone this only means they've reached Wolverhampton which is of no use to them as it needs to be on their system by the 17th of this month. Eh???? How is that my problem?? I've been to citizens advice, they told me I should be entitled to all both elements at a higher rate from my evidence, but that's no good to me if they are saying they're not receiving it! I live in the north and my carer offered to DRIVE to Wolverhampton to physically give them a copy and they said no. Has anyone else had this issue? I'm terrified my pip will stop now. I'm due a payment just after their end date they gave me on my form and they're saying it's my problem they don't scan them on quick enough? Surely that's not right.