Born overseas - issues with birth certificate

[withaspongeandarustyspanner]

I was born overseas in 1973 - my father was in the armed forces. I was very much born into a British colony. I have a birth certificate issued by the authorities at the time. From time to time, I get questions about it, but I have been able to use it to get a passport/driving licence/DBS check etc.

Until today.

I am trying to sign up to a supply agency to be told that they have checked with compliance and my birth certificate is not valid. They will take a marriage certificate (even thought I am divorced and that actually isn't valid and you have to surrender it when you get start divorce proceedings).

I feel they are being ridiculous. Are they?

Do they say why they think it isn't valid?

I feel you OP! They are ridiculous. But they think you are forrin. I'm four years younger that than you. My British father worked abroad for the British Government. I have a British passport and dare I say - am British. I was denied entry to a "secure" work site in 2019 "Because you're Spanish." - not the country but you get the picture.