Visitor Visa - B2

Case History: I have been issued a B1/B2 visa from India in 2017 year for 10 years. I went to the USA for 34 days and came back to India. In the following year, the embassy called me to the consulate in India and interviewed me again, kept my passport with them, and cancelled my visa. As I did nothing wrong during my visit to the USA, no crime, no overstay, and no work, but, for unknown reasons they cancelled my visa. They asked me to apply again if I wanted to.

I applied for my visa for the same visa again in India but again refused without asking any questions in the interview.
Then, I moved to Australia and did my did study here, then again I tried to apply for visa, the VO gave me 221g and told me that there was nothing wrong with my profile but on the very next day, I received a 214b refusal through email.

 This year, I applied again for same visa, and got interviewed again, and all went good in the interview, VO just want to know why my visa got cancelled as he didn't find anything wrong with my profile, said me that he has review my case in detail and given me 221g and returned my passport as well.

After 15 days, I got an email that they are ready to continue my visa application and require my passport. I sent my passport to embassy and my CEAC status got changed from Refused to Administrative Processing. Its been 4 days today including saturday and sunday, there has been no update on CEAC.

Just worried what is going on?
if somebody have same experience, can you please share?

Thanks.