Thanks! Will try to add, and waiting for resultIf the number you entered in the blacklist does not match the exact caller id of the incoming call, it will not match. Try using a wildcard such as instead of having 123456789 in the blacklist, put *123456789.
Ohhh ... separated rule for every "smart caller", lots of honorYou need to look at the activity log, and see what number is being presented to 3CX.
Instead of using blacklist, which is for IP addresses (call may be coming from multiple IP's) you need to create a CID rule to drop the call.
Thanks! Added.As mentioned by ChrisC_3CX enter *48797836055 as the number
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