in a outbound campaign,  some number would be failed to be reached, like no answer,  hangup caused by bad voice quality, so we need to dial these numbers again, then we provide the  auto recycle feature.

Max trytime:  the maximum time we will try, if we have dialed the number more than a number, it would not dial any more

Recyle time: when to recyle the number, 3600 means  it will recycle the number after 3600 seconds if it dialed last time.

Min Duration: if the talking time is  equal or less than the min duration, it will be recycled.

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