Johnson Controls R2R interview questions

I was interviewed mid of Mar'21, it's 4 round of interview, it took nearly 1 month. After qualifying all the round I was asked to collect the required documents to issue final joining letter. It's been 2.5 month elapsed but no response from their end, unnecessarily I wasted my time. HR also not intimating as I tried several time but no response. Exactly I don't know the reason behind holding my profile.