Panasonic Quality Engineer interview questions

First was phone interview, then the HR lead me to 1:1 interview in the office. A day after 1:1 interview, I had an e-mail from the HR that I have been selected for the position and the offer will be sent to me. However, the offer never come. Tried to follow up after 1 month 2 times by phone, HR keep saying will get back to me but never do it. E-mail also no response, no rejection notice.