Multiple External Priced Promotions not applying correctly

Summary:

Let's say my item total is 1499, external shipping to the value of 215.48 (Order Total of 1714.48). External promotions calculations are triggered which returns 2 qualifying promotions:

[

    {

        "coupon": "",

        "adjustmentAmount": "-215.48",

        "adjustmentOperation": "adjustOrderPrice",

        "description": "Free Delivery Promo",

        "displayName": "Free Delivery Promo",

        "promotionId": "123456789"

    },

    {

        "coupon": "HC1300",

        "adjustmentAmount": "-1300",

        "adjustmentOperation": "adjustOrderPrice",

        "description": "Voucher Code",

        "displayName": "HC1300",

        "promotionId": "234567891"

    }

]

The expected Order Total after applying the above should be 199. However, this isn't the case. On OCC on the Price response after applying the Voucher it calculates the wrong overall discount. It shows a final total of 215.48. It seems like the second promotion discount does not allow the order total to go less than or equal to the first promotion adjustmentAmount. As soon as I make the adjustmentAmount of the second promotion equal to or more than 215.48, it calculates the order total to be 215.48 (first promotion).