I had a similar experience with a Yealink T54W and I found this thread to be very helpful. I provisioned a T54W and as soon as it connected I got the IP got blacklisted error. I am still having problems though.
- I reset my T54W
- I uploaded the 3CX suggested firmware 96.86.0.74
- I changed my IP address and logged in to my managed free 10 user account
- I removed the T54W IP phone from the account.
I can register (provision?) the phone again when I am on another network, it shows my extension and it works. When I switch my computer, back to the original IP address, it still blocked, and I can't log into 3CX.
I wend back to the different network, logged in, and I removed the phone again and even with no hard phone attached to my account I still can't use 3CX on the original network.
I am assuming there is no dashboard in 3CX with the free hosted solution, or is that a different location than the 1248.3cx.cloud webclient login? I found this
https://www.3cx.com/docs/allow-deny-ip-addresses/ but I don't see this in the webclient.
Is there another way to whitelist my IP address?
Does 3CX have this dashboard on a hosted system, or is that the vendor that got assigned my account if I want to upgrade?
Do I need to pay for support to get this unlocked?
thanks
-david