It's not a cultural practise for me it is a religious requirement
It’s not a religious requirement, is it, since most Muslim women do not wear niqab? It seems like a personal commitment you’ve made.
But the hijab is compulsory in places like Iran for women to simply appear in public, regardless of their religious affiliation. There are still religious minorities in Iran, like Jews, Christians and Zoroastrians. And ISIS compelled women to wear the niqab, Afghanistan compelled women to wear the burka (again, religious minorities typically not exempt from these requirements).
As for the UK, I assume it has freedom of religion. I wouldn’t know the details, I’m not from there. But it has limits, doesn’t it? You can’t practice polygamy there, for one.
But niqab seems to me a cultural practice, since the Quran is quite vague on this topic and the niqab pre-dates Islam anyway