give chance to approver for send mail for correction to previous level i.e's reviewer is it possible. in case it's possible how we have to achieve that.
I am not quite sure what you are asking. Let me say what I "think" you are saying. There are 4 approvers:
You want each approver if they reject it to be able to send it back to the previous approver for correction. If this is correct you can do this.
You can create a state machine with the branches for each of the approvers. In each branch of the state, you have a flexi-task where the approver can approve or reject. If the person rejects, send email notification and then you change the state (using the Change State action) to the previous approver. If not, you change the state to the next approver.
Hopefully you understand this.
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