Pepmaco Manufacturing interview questions

It was going well with the hiring manager and head office hr. They even offered me a role and discuss. But upon going to Plant HR something was off, and suddently did not push through to meet the President after talking to plant HR. The process was confusing as there is no really schedule or advise that plant HR will talk to me. Then they already got my compen ben and ready to offer but then sudden no reply for week then just a thank you/rejection email after. They wasted my time with sudden change in decision of hiring, after letting you feel you will get the role already