Advice needed re pip mess

Where do I start with this, my pip claim was due in on 8th Nov due to form arriving late and an operation being canceled I was granted extension to the 22 November.

Got my forms all filled in and just needed evidence and firm photocopying so I dident send original letters etc.
I had planned to do this on Wednesday 11th Nov.
Unfortunately on the Tuesday I was taken to hospital by ambulance with right pupil fully dialated ( still no idea why it happened)
Sent home later that night with urgent app at hospital next day.
Got to hospital and they booked urgent ct scan .
On way home taxi was rear ended on dual carriageway.
Ambulance back to A&E
Discharged 4 hours later mith majorly aggravated pre existing issues.

Fast forward to the 18h its posted special delivery 1pm so should have arrived on the Thursday.
Hosptal Thursday and very bad night with flashbacks and pain I stupidly dident check it had arrived via tracking.
Checked about hour ago and it's been stuck at the North West Midlands mc since 3.28 am in the 19th.

I currently am shaking feel sick and don't know what to do, not able to get hold of anyone at pip or RM

You have proof of postage.
Delay is fault of Royal Mail.
You should be able to send an official complaint by email to This email address is being protected from spambots. You need JavaScript enabled to view it.
They must convince the DWP to accept your claim late as they are resonsible for it being late. They entered into a contract with you to deliver it by the time stated. If they fail they will have to compensate you.
You may have to start a fresh claim if DWP do not allow an extension due to circumstances beyond your control. You can fight such a decision by appeal.

Update,
Got through to RM first thing and their tracking system was interrupted slightly but they explained that it has been accepted and delivered to bulk mail site.

Spoke to pip claims and it was scanned onto system at 11.24 on 20th.
Due to how their system works it buggers up the RM tracking.

So if anyone ends up in a total tizwoz like I did its likely that it's simply dwp not updating dye to 1000s of bits of tracked mail.

Now the battle begins.......