When you're first invited to PayHero simply click 'Accept Invite' in your email invitation to join your company's PayHero account.
If you already have a PayHero account (or another FlexiTime Workforce Management account through Droppah) associated with your email address, you'll be taken to the 'Confirm your password' screen instead, with only one password field available.
Simply enter the password you already use and click Accept Invite - your new invite will be joined to your existing access. You'll then be able to switch between your PayHero accounts (or other FlexiTime Workforce Management accounts), as shown here: Using Multiple PayHero Accounts
If you've forgotten the password you used previously, you can first request a password reset as shown here: How Do I Login?
Once your password has been reset, you can complete the acceptance of your invite with the new password.