In case an element A is behind element B voting on element A can only be added but not changed
In this case, if you click on element A in the voting session a vote will be added. But hovering over the existing vote does not offer the + / - option to change your vote. If you move element A into the upper most layer of elements it is possible.
Hi Rainer!
I was not able to reproduce the same issue on my end. It looks like your issue needs a bit more investigating on our side, so I have created a support ticket for you.
Our Support team will get back to you via email as soon as possible! :)
I hope this helps! 
My support:
Under the link https://juropera.com/wp-content/uploads/2022/01/MiroBugVoting.mp4 you will find a video where I demonstrate the bug in Miro. I hope that helps.
Feel free to contact me under rg@juropera.com or rainer@pragmatic-solutions.ch
Best Rainer.
Your Answer: (see below for my answer….)
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Elizaveta (Miro Support & Help Center)
Jan 6, 2022, 11:59 GMT+5
Hi Rainer,
Thanks for reaching out and reporting the issue! We're very sorry you've run into it!
Please, take the following steps to Reset the Desktop App data on your device:
When you load the dashboard, press Alt and click Reset application data as shown on the screenshot below:
If you cannot find the menu, you probably use the app downloaded from the Microsoft Store. In this case, to reset the app data, open Windows Settings > Apps > Apps and Features > find Miro on the list > Advanced options > Reset.
After that, log in to the Miro desktop app, try to vote again, and share your results with us.
If the issue persists, please delete the Miro app from your system and download the latest version from here: https://miro.com/apps/.
Does it help? Looking forward to your reply!
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Hi Elizaveta,
I am sorry, but that did not help. The bug still exists.
Best Rainer
Enter your username or e-mail address. We'll send you an e-mail with instructions to reset your password.