There are a few reasons why you could be experiencing this issue! Pixieset Passwords are both case and space sensitive. Your clients will need to enter the Passwords exactly how you have entered them in on your end or the system will not recognize it as the valid password.
The biggest error with Collection Passwords is there being a hidden "space" within the Password. When looking at the password itself from both your end, and the client's end, you wont be able to tell that there is a space located within the Password.
Here is how to tell if you've accidentally entered a space:
Go to the Collection > Collection Settings > Password
Simply click the password bar where you would type in the password itself. It will light up blue, and you will see your cursor begin to blink.
If you can see a space between the word and the cursor or " | " symbol, then you have accidentally entered a space with this password.
Simply hit Backspace or Delete to remove the space, once this is done successfully the cursor symbol should appear to be touching the word:
Once your password is successfully saved without a space your clients will now be able to access the Collection no problem! However, make sure that they do not have any cached information saved about the original password on their browser, or they may continue to experience the issue due to their browser auto loading the original information.
If you continue to experience password issues, contact support at firstname.lastname@example.org!