British consulates and embassies cannot provide support for non British nationals unless they fit into categories below, even if they legally reside in the UK.
Support for British Nationals Abroad: Summary from WWW.GOV.UK
We can provide the support set out in this guide to people outside the
UK who are:British nationals (whether or not they normally live in the UK – see
page 6 of main guide)British nationals with another nationality (known as ‘dual nationals’
– see page 6 of main guide), although this will depend on the
circumstances – normally we cannot help dual nationals when they are
in the country of their other nationalityNationals of European Union Member States without a local embassy or
consulateNationals of other Commonwealth countries where there is not a local
embassy, but only in certain circumstances (see page 6 of main guide)We cannot provide this support to other countries’ nationals, even if they have been living legally in the UK
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