Hi njkeb96
Unfortunately there is no way to block incoming calls from specific numbers.
You can try to advise this person that she or he is doing a criminal act and that you will inform the police if she or he doesn't stop harassing you.
If this would by unsuccessfully, we recommend you to proceed with a phone number change.
Please call our hotline to get more information: 0800 800 800.
Kindly regards
TizianaD