FedEx has blamed a spike in passport applications for not getting the documents to travellers in time.
The company said that as restrictions on going abroad were slowly rolled back, passport applications have increased.
The company’s subsidiary TNT has an exclusive contract with HM Passport Office (HMPO) which is worth £77 million over three years.
But on Wednesday the Times reported that it has been struggling to reach customers in time, even if they have paid for express services.
“As Covid-19 restrictions have continued to ease, HM passport applications have increased. This has resulted in a significant increase in the items to be delivered through our dedicated HMPO network,” FedEx said.
“For some customers, this has meant an extended delivery service from what would normally be a two-day service.”
A petition to investigate what due diligence was done on TNT before it was awarded the contract and why it has not been stripped of the service has gained 233 signatures on Change.org.
The petition’s organiser wrote: “Many have had to cancel their travel plans as a result and lost out on hundreds or even thousands of pounds.
“Unlike many other couriers, TNT do not seem to provide real time tracking, nor can you provide delivery instructions.
“People have experienced numerous failed delivery attempts, others have had their delivery date continuously pushed back with no end in sight. Some have even had their passport or application supporting documents lost by TNT.”
FedEx added: “We fully understand the importance of these shipments to our customers and are taking additional steps to provide timely delivery by adding additional resources to the operations in the UK.
“We’re also working closely with HMPO to ensure recipients are informed of potential extended delivery times.
“We are also aware of some additional reported issues from customers related to missed deliveries and we continue to work closely with HMPO to resolve these.
“We apologise for any inconvenience caused.”