Hi Saqqara,Need alot more info on your setup - please provide info as per post https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/
Make sure you can pass the firewall checker and please keep in mind that IP based providers always appear online (green) in 3CX as there is no registration to indicate otherwise.Looks like there seems to be a problem with the Firewall Firewall Checker failed
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