Thanks for coming by and welcome to the community.
There are various things that can be tried. Some of them are listed here: Unwanted, nuisance or malicious calls on your Virgin Phone.
If they are calls from outside of the UK they can be trickier.
There are some handsets that can be purchased that block individual numbers which may be worth exploring. (Assuming you don't have one already).
I hope this helps, if you have any further queries, please don't hesitate to ask.
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