I had a major issue with BlueHost Hosting recently where a simple task like adding a nameserver did not work correctly and I had to follow it up many times using chat support.
Normally a nameserver change is reflected in 30 mins to 4 hours and it may take upto 48 hours at max. But in my case nameservers took 6-7 days to propagate and this happened multiple times with multiple domains.
On the first instance they blamed GoDaddy, so I had a discussion with Godaddy support regarding the DNS problems. They clarified it with proof that it was nothing that they control as the nameservers are from Bluehost and only they are answerable why it is taking so long to propagate.
I used many open DNS checkers out there and only a few countries would report positive DNS update. On day 3 only 3 countries had the right DNS. On day four it increased to 4. On day 5 it increased to 6. On day 6 it was available in 10 countries but not in USA yet where the bluehost servers are located. So I still could not add an addon domain to my hosting. Finally on 6th or 7th day the DNS propagated to USA and we could add a domain.
This issue repeated in the next addon-domain addition. This time BlueHost was quick to blame Network Solutions for the problem. I blasted the idiot chat executive and told him I had had enough of their bullshit. So he told me please contact again after 6 hours when a domain expert is available.
Here is the chat transcript of the entire discussion.