Partners (TX) interview questions

Was contacted by HR to have a phone screening. Was essentially told I was a great candidate and then asked when I could start. At the end of the call, I was told that I would have an assessment scheduled to display my skills and after waiting and not receiving the assessment, I called and they had no clue who I was and then said they would call me back. Then received an email stating sorry for the mix up we aren't interested. I'm fine being rejected from an opportunity, but have clear communication with candidates. I sat around waiting for an assessment that was told to me over the phone that I was scheduled for, it wasted my time and was unprofessional that I did not receive a notice that they were canceling it or that I was taken out of consideration.