Trello will be using Atlassian accounts for login and for your profile. They have created an Atlassian account for you with the profile from your Trello account.
If you get a banner notice from Trello, as seen below, please read through the Atlassian provided FAQ.
- Confirm that your account is just for APU and that you wish to log in with Atlassian.
- Confirm your account, we recommend using your Google Account.
- They will confirm that your Atlassian and Trello accounts are now connected.