sons lost passport papers

i am looking for advice to a major problem
i applied for a renewel of my british passport and the first passport for my son age 11 at the same  time  date applied 30 march 2015 bangkok office said my passport had arrived and i received a letter to confirm this i emailed liverpool to ask about my sons passport and they said they needed more info about my son ie family photos any maternity papers and photo copys of my wife s passport and mine when david was born i emailed saying i would take everthing they  asked for to the bangkok office when i picked up my passport they already had all the papers concerning david and any thai papers translated which they asked for that where checked and i received a signed receipt for from the 30 march 2015
back to bangkok to pick up my passport and hand in more documents and family photos of david the photos they kept and the maternity papers they kept not photo copys and they
gave me a signed and listed receipt for the documents dated the 12 may  2015
july 7 2015 emailed any news sons passport
liverpool reply answer overseas checks july 8 2015/ alarm bells ringing/
aug 3/ 2015 liverpool nothing showing on our com send dhl tracking no
aug 4 emailed all numbers dhl has asked by liverpool
aug 26 emailed liverpool any news
same day reply application withdrawn timed out since when is there a time limit on apply for a passport
i even received a letter from liverpool telling me my money would not be refunded and would go towards postal costs this has being a running problem with liverpool they said i had not sent the papers they would not admit they could be wrong
now i no the truth the papers where deliverd to liverpool passport post office i have the dhl delivery document in front of me signed by the liverpool post office has received on the 14 may 2015 at 12.27
i have also received an email telling me they cannot find my papers they have lost them and searched in all there files in liverpool office
also a letter to get a refund of my money which they said was an overpayment
i also received a letter dated 20/ 4/2016 saying can you list the times you went to our bankok office and why
please can you list all the original  documents supplied by you to bangkok vac and are now unaccounted for
and i love this
as all payments made by hm passport office must be auditable and justifiable were you are unable to provide receipts as requested on the 11 april 'hm passport office will accept bank or credit cards detailing the expenses as a result of misinformation or errors by hm passport office staff
yes and i kept receipts no i did not imagine my papers would be lost i have had iyear of this problem i pay cash for every thing this is thailand  except my sons passport credit card and what price do they put on the anguish caused by there mistakes also the loss of 9 family photos  and davids and my wifes maternity book from blackpool victoria hospital all original how can these be replaced they can never be replaced ask my wife
and it does not get better
hm passport office are unable to consider reimbursement of costs for essentials such as food and drink
has they say that takes the biscuit
can anybody please help me and my son all i wanted was a passport now its turned into a nightmare i am looking for legal help any good advice is welcome
kind regards for any help vincent costello