Issue with Coupon Code not calculating discount properly

[DinaLRosenberg]

We have a coupon code, "TikTok" that gives customers 15% off their online purchase in pretty much every category we offer EXCEPT classes & events.

We recently received a message from a customer that the coupon was not taking off the proper amount.

Trouble Shooting Done So Far:

I went into my coupons on the online side to check all the settings. They are correct.

I went into each individual item the customer was trying to purchase to check that the were assigned a category that was eligible for discount. They are.

I went into coupons in square marketing side and noticed something alarming:

there is no way to edit or check. particular coupon

Please see attached photo of the customer's order. $4.20 is NOT the appropriate discount 

[Candlestore]

@DinaLRosenberg ;

Discount of $4.20 reads "Get 15% off an Item...."   

So on that receipt is there something for $28?  15% off of 28 would be 4.20.

I do not know why or Square thought on how the discount is applied (Highest or Lowest priced Item) or the first one in Alphabetical order.  Does the Customer choose which item to apply it to?

If the Discount Coupon read off your next order I would expect almost a $15 discount but since its off an Item I understand the $4.20 discount if an item is about $28 on that receipt.