When trying to clone a repository, getting an error message of "Not a valid source path"

Hi there,

I am trying to clone a repostiory from GitHub.

Here is the repository:  https://github.bedbath.com/BBBYOrg/bbbAssets

When I open sourcetree and add this to the Source URL in the Clone tab and attempt to clone to my local machine, it gives me an error of "This is not a valid source path/URL".  When I click the error details, a box opens with this content:

Command: perl.exe C:\Users\na0145\AppData\Local\SourceTree\app-3.0.8\tools\svn.pl info https://github.bedbath.com/BBBYOrg/bbbAssets
Output:
Error: System.ComponentModel.Win32Exception: The system cannot find the file specified

Command: hg identify extensions.hgext.hgsubversion=! https://github.bedbath.com/BBBYOrg/bbbAssets
Output:
Error: abort: HTTP Error 406: Not Acceptable

Command: git -c diff.mnemonicprefix=false -c core.quotepath=false --no-optional-locks -c credential.helper= -c credential.helper="C:/Users/na0145/AppData/Local/ATLASS~1/SOURCE~1/GIT_EX~1/GIT-CR~1.EXE" ls-remote https://github.bedbath.com/BBBYOrg/bbbAssets
Output:
Error: remote: Invalid username or password.
fatal: Authentication failed for 'https://github.bedbath.com/BBBYOrg/bbbAssets/'

I have tried resetting my Atlassian password and haven't been successful in cloning this repository.  

Any help would be appreciated!