Blocked calls to voicemail?

Hi,
Just wondered why calls showing as blocked calls, still manage to go to voicemail?
I am getting the same number call me at least twice per day, the call is blocked and reported, yet they still go to voicemail and so I then get vm notifications each time 🤨
Anyone know how to block them completely, I've tried all the obvious options.
Thanks

AndyPFx - are the numbers from Spam callers?

I suspect this is likely because when we block calls we typically do it on our phones, which does exactly that, it blocks the call coming through to your phone. Networks still accept the call though so, to stop these getting through to your voicemail too maybe take a look at your My Lebara account and activate your Call Filter if you haven't already - this should help to stop receiving unwanted calls.

Thanks Nick.
Well I've only noticed it with this one particular number, and since I switched to Lebara.
I have lots of blocked numbers listed on my phone, but only that one that goes straight to voicemail.
So I was thinking there must be something different.
If a call is blocked, surely it shouldn't be sent to VM, as that is just as annoying to have to delete blank VM msges 🤨
I will also look at the filters as you suggest.
Thanks again.
Andy