<span style="font-family: Arial, Helvetica, Sans-Serif; font-size: 12px"><div>If you have not done so contact the carrier immediately. Report the fraud.</div>
<div>Have them disable international on the account until you have your security issues addressed.</div>
<div>Ask them to pull call logs containing Source and destination IP address. for the fraud calls.</div>
<div>If you are sure they came from your systems IP address then verify the systems does not have any unauthorized registered endpoints.</div>
<div>Verify the source and destination of the calls from any internal logs.</div>
<div> </div>
<div>If the calls came from your IP then you are likely on the hook for the calls. If they came from another IP that you don't own then if you can prove you had no access to that IP than there is some hope the carrier may work with you.</div>
<div> </div>
<div> </div>
<div>Thanks<br />
<br />
Bryant </div>
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