PIP problems

transfer from DLA to PIP letter in May, form applied for, never arrrived, another form sent out and returned. Letter from CAPITA 2nd July confirming same etc. Nothing more heard, DLA still coming in so not cancelled. Phone up today - end of OCT. Capita notified of a change of address for me, sent forms back to DWP. I have lived here for 10 years now - no change of address. Apparently a CoA (an old address from 10 years ago)was notified from tax office - due to a mix up on National Insurance database. DWP assigned my claim to another assessor ATOS - no mail to either my address or my old address(which was my sisters address) consequently my info stuck in limbo - DWP now on the case again - I hope someone eventually manages to sort out their admin problems and procedures. I can't take much more...