What should I do about these strange harassment calls from an unknown caller?

Hi all,

I have had a UK phone number for two years since moving from abroad.

About half a year ago I (27F) started to receive calls and voicemails from an unknown number. It’s a man, possibly older middle age, with a heavy British dialect which I can’t understand a word of.

I’ve only used my phone number for work, and for registering on online orders or other normal things. Very few people have my number at all, which made me think it was a case of a wrong number.

I’ve tried to save some voicemails and show them to my British partner, but he can’t understand anything he’s saying either.

I don’t recognise the voice or the number, and a search online produces zero results on Google.

He always calls late at night, sometimes in the early hours of the morning and rambles on for about twenty seconds before hanging up. From what I can pick apart, it seems like he’s saying that he misses me, other times he seems angry and says that he doesn’t want to know me. He’s calling every two weeks, sometimes days apart.

I’ve tried calling the number to ask him to stop calling me, I have tried texting him to explain that he has the wrong number and that I don’t know who he is, I’ve threatened to report him and I’ve asked who he is. He’s answered just once, and it was somewhat cryptic and nonsensical, asking me to bring over some sugar with a “x” at the end. I have no idea what this is supposed to mean.

I’ve blocked the number but it seems that I’m somehow still receiving calls and voicemails, so I’m a bit unsure how this is happening. Perhaps there are different phone numbers or it’s just flagging him up when he calls? (He’s currently showing up flagged as spam and the log says blocked number.)

I thought blocking would be fine, but it seems this isn’t effective. Now I’m a bit unsure what to do. Is this something the telephone service provider could help with? The whole thing seems bizarre.