My mother and grandmother are from Montserrat and my siblings i was born in the commonwealth territory?

Antigua and Barbuda in 1973 before Antigua and Barbuda got its independence from UK . I grew up in UK Territory(Montserrat) and always had a UK territory pport. In 2004 my UK oversees pport expired and i sent my pport to Montserrat to be renewed but they kept my pport. I need some info about me getting back my UK oversees pport. i have always travelled on this pport now i dont have one. any suggestion iswelcomed