You have two options to change the number of votes. The first one is when creating the board. And the second one is after creating the board.
Here are the steps you need to follow to change the number of votes.:
First Option: When creating the board
Step 1. On your Dashboard page, click on the “Add Board” button.
Final Step. Below the board's name, you can add the “Max votes per user.”
Second Option: After creating the board
Step 1. Click on the clockwork icon (settings).
Final Step. Find the “Max votes” feature. Change/add the votes there. You can click on the “+” sign to increase or the “-“ sign to decrease the number of votes per user.
Note: You can now decide if the Max votes are per board or column.