I am a Briton living in Switzerland and my three children are British and Swiss nationals.

When we found out via the Guardian that dual nationals, who live overseas, are now required to hold a British passport in order to enter the UK, we set about applying, so the children can continue to visit their English relatives.

More than three months later we find ourselves in a nightmare with HM Passport Office (HMPO).

We have provided all of the documents asked for, including three different birth certificates for each child (British, Swiss and a certified translation), we have spent countless hours on online helplines, and spent close to £800 on fees, translations and postage – to no avail in the case of our youngest child. His application has been refused despite the fact his siblings’ were accepted on the strength of the same documents.

We now have to send antenatal records of his birth eight years ago, as well as our passports valid at the time of his conception. Those passports have long since expired and been replaced.

We are taking the children to visit their grandmother in England in July, but it looks as though my son will be barred entry into his homeland.

KCG, Unterseen

The new rules came into force on 25 February and have led to UK nationals being stranded abroad, to families being split up at airports, and to expats being unable to attend weddings or sickbeds in their homeland. Those who don’t have a British passport must fork out £589 for a “certificate of entitlement”.

It seems bonkers that your Swiss wife, not a dual national, can travel to the UK on her Swiss passport with a £16 electronic travel authorisation, while your son can’t.

In lieu of your son’s Swiss birth certificate, which HMPO unaccountably refused to accept, it requested, among other things, a sequence of original photos of him with both parents from birth until now.

When I questioned HMPO about its refusal of documents accepted for your two other children, it suddenly messaged you to say the passport had been printed. It did not reply to my request for a comment.

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