Block not works on mobile phones

Hello,
I like Yop Poll.

Now, I created after a long time a new poll.
In this poll I will block users to vote only once.
On PC this works perfect.

But when I display my post with Yop Poll on mobile phone, the voting is not disabled. But when I try to vote from that mobile phone again, the Yop Poll ansvers correct, that I already voted (my localized message will be displayed).
So the Yop Poll knows, that I already voted, but enables voting on mobile and this is not correct.

I use newest versions of WordPress and Yop Poll on OceanWP theme without child theme modifications. The poll is placed in a post (not on a page).

Poll settings: basic template Green V4, Load using AJAX: No, Reset Poll Stats automatically: No, Use Captha: No, Vote Permissions: Guest, Block Voters: By Ip, Block Period: Forever, Limit Number Of Votes per User: No (I tried both: yes and no), Show Results: Befor Vote, After Vote (this works), Show results to: Guests, Registered.

Thank you,
Radomir

The page I need help with: [log in to see the link]