First of all, don't post a new question. Simply reply to the question you originally posted to so that I'll get notified. Secondly, delete the "opportunity record" Approval Process and give me screenshots of your Approval Process.
Try fixing your criteria to Opportunity Stage equals Awaiting Approval, and Discount does not equal 0. Also, change the assigned approver from you to the record owner, don't hard code yourself into it. If that doesn't work, then let me take a look at your field update action details.
Could you please elaborate your issue clearly, so that it helps us to resolve your issue asap.
Best Regards,
Nagendra.P
i got that error plz tel me detail steps procedure for this question
i have that approval process what is the correct steps detaily tel me sir