1) Welcome to the Party!
2) when you post, please post your entire configuration including (but not limited to) your installation method and vicidial version with build.
this IS a requirement for posting along with reading the stickies (at the top of each forum) and the manager's manual (available on EFLO.net, both free and paid versions)
You should also post: Asterisk version, telephony hardware (model number is helpful here), cluster information if you have one, and whether any other software is installed in the box. If your installation method is "from scratch" you must post your operating system and should also post the .iso version from which you installed your original operating system.
If this is a "Cloud" or "Virtual" server, please note the technology involved along with the version of that techology (ie: VMware Server Version 2.0.2). If it is not, merely stating the Motherboard model # and CPU would be helpful.
Similar to This:
Vicibox X.X from .iso | Vicidial X.X.X-XXX Build XXXXXX-XXXX | Asterisk X.X.X | Single Server | No Digium/Sangoma Hardware | No Extra Software After Installation | Intel DG35EC | Core2Quad Q6600
3) Let me see if I understand your statement: You receive phone calls from numbers you did not call? Have you talked with any of these people to see if it is simply that the numbers are forwarded to other numbers? How often does it happen? (1 per week, 3 per hour ...?) As a percentage of inbound calls, how many are from numbers you did not call? (Obviously if it is less than 1% it's just forwarded numbers and those who called from their office phone to avoid minutes on their cell ... but if it's 75% you may have an issue).