SFTP-SSH Connection Will Not Update

I'm trying to create a new connection with the SFTP-SSH action in a flow that triggers when a new file is added to a folder on a client's FTP folder. In filling out the new connection I'm populating the -

• Connection name
• Host server address: files.blackbaudhosting.com
• User name: [User Name from ‘FTP access account information’ tile]
• Password: [Password from ‘FTP access account information’ tile]
• Port number: 22

Is there anything I'm missing? It keeps returning this error code:

Test connection failed. Details: SSH host key finger print should be provided when the SSH host key validation is enabled.

Not sure if it matters, but the database is hosted on a Blackbaud server.