A group representing nightclub owners says Scotland’s vaccine passport app is “not fit for purpose” and led to “chaos and confusion” on the first day of the certification system.
The scheme began officially in the early hours of Friday, though enforcement will not begin until October 18.
Clubs have been asked to check the vaccine status of customers before they enter.
The NHS Scotland Covid Status app launched on Thursday but technical issues meant many users could not access their vaccine certification.
The Scottish Government has said the delay in enforcement means no-one should be turned away from nightclub doors this weekend.
On Saturday, the Night Time Industries Association (NTIA) said venues all over Scotland had reported “high levels of customer frustration over the lack of information from government and chaotic rollout of the app”.
It added: “It has become very clear that the Scottish app is simply not fit for purpose and the vast majority of people are experiencing repeated problems in registering and uploading their personal vaccine status to the app.”
The industry body opposed the introduction of the vaccine passport scheme, which the Scottish Government hopes will encourage uptake of the jab.
Mike Grieve, chairman of NTIA Scotland and director of the Sub Club in Glasgow, said many customers were presenting the wrong type of vaccine certification at the door.
He said: “As anticipated, the rollout of this ill-conceived policy led to chaos and confusion in the street last night with only a handful of our customers in possession of a functioning app passport.
“Around 50 to 60 others had a photocopy or screenshot of the wrong vaccination information or other spurious evidence of vaccination.
“Despite this we successfully checked all attendees for same-day LFTs (lateral flow tests) to protect the health and safety of our customers and staff.
“What a shambles.”
The NTIA went to the Court of Session to try to halt the vaccine passport scheme, earlier in the week, but were unsuccessful.
The Scottish Government said early issues with the app were due to a high number of users trying to access data at once.
The government apologised and said capacity in the NHS systems behind the app had been increased.
On Friday, health secretary Humza Yousaf said the issues should be solved “if not within hours, then certainly within days”.
He told Bauer Radio: “If you’re planning on going out to a nightclub tonight or go to the football at the weekend, still go.
“Because of course we delayed enforcement of the certification scheme, to make sure the system had time to bed in – to test it.
“Therefore there’s nothing within the regulations that means you should be turned away from the nightclub door or turned away from the turnstiles this weekend.”
A Scottish Government spokeswoman said on Saturday: “We have had extensive discussions with stakeholders over the last month and introduced the grace period in response to their feedback to allow the system to be tested.
“We have also provided detailed guidance for venues and the public which we will keep up to date.”
She continued: “There are no plans to delay the coming into force of the enforcement provisions.
“In total, 167,600 people have now downloaded the app since its launch.
“We are aware of some teething issues which are primarily down to the volume of requests, the work that has already taken place has resolved many of the issues people have been experiencing.
“We expect any residual problems to be fixed shortly.”