TLDR: When you create polls, you can decide if your users are allowed to change their vote or not. The default is in your settings, but the default can be changed in the /poll command or in Edit mode.

Now for more details:

What are ‘Vote Change’ options?

When you create or edit a poll, you decide if users can change their vote or not.

• Vote Change: 🚫Not allowed → your users’ vote is final. They can’t remove a previous vote or change their vote.
• ↩️ Vote Change: allowed → your users can change their vote by clicking on another option (single-select) or by deleting the previous vote by clicking on it again

Select the ‘Vote Change’ option in the /poll command

Edit ‘Vote Change’ in Edit mode

• Go to Edit mode with /edit or from /home > View/Edit
• The current option will show under ‘Options’:

• If you Edit Vote Change,you can select yes to allow your users to change their vote

• The new setting will show in the survey summary

↩️Vote change allowed is now mentioned in the poll embed