Thanks for your question. I will try to help.
Obviously, your children are not automatically eligible for UK citizenship because you are already a UK citizen by descent.
This means that the only way that they could apply for citizenship would be if they were able to register under the British natilnality Act.
There are two ways that this is done, the first would be if you had spent three years in the UK without leaving for 270 days. This is not an option.
The other way would be if you now lived in the UK with them for three years without leaving for more than 270 days. You could then register them as UK citizens under section 3(5) of the British Nationality Act 1981 and, once registered, apply for their passport.
These are the only options. They are disclosed on the passport forms, because they are the law and the government has a responsibility to disclose such rights.
I am sorry I could not have better news for you.
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