Is this company legally justified?

i applied to a company and went through the hiring process, i was even drug tested and passed the test. when i was asked to bring in my paper work ( id, ssc,birth cert. and hs diploma)i informed the manager that i didnt have my hs diploma, which i stated in the application. he told me that i couldnt start until i had it, so now a few weeks later i have it, i called him, and he claims i was never hired and i have to wait because they have alot of things going on, the company is allied barton. my question is are they justified legally?