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Note:- When topping up the campaign, make sure that the columns of the uploaded file matches the one used to originally create the campaign.
Recycle
Recycling of a campaign provides the ability to remove specific dispositions from a lead's history. When you recycle a campaign, you have the option to select which specific dispositions in the lead to recycle from that dispositions is an easy and manual way of resetting previously dispositioned leads back to a status of Open. This will put the leads back in the campaign and the leads will be called again by the agents working in the campaign.
For instance, you can recycle all leads from a campaign that have been dispositioned as Not Interested and the affected leads will all go back from being in a Closed state to being Open once more.
When you select the Recycle option, a window similar similar to the screenshot below will pop up appear and you will then have the ability to recycle the leads based on the dispositions you have selected. 
However, note that the dispositions to be recycled will be based on the specific dispositions of your organization and may appear differently than shown below.
An example of how the lead history of a recycled lead will look as follows:
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