Many expats confuse residence and domicile.
Changing residence is easy, leaving the country for a certain number of days generally does the trick.
Domicile is different. It isn’t based on where you live. It is based on where you or your father were born or raised. If this was in the UK, then you are likely to be deemed domiciled in the UK.
Domicile is insanely difficult to change and if HMRC deems that you are domiciled in the UK, they will come after your worldwide assets for inheritance tax (IHT) when you’re gone.