Shipping profiles can definitely get tricky, especially when you’re trying to create custom increments. For your first question, it usually works best to build the profile using clear quantity or weight ranges, but sometimes the ranges auto-adjust depending on how the previous tier was entered, so double-check that each range starts exactly where the last one ends without overlap.
For your second question, if items are pulling shipping separately, it’s often because they’re assigned to different shipping groups or profiles, so Square treats them as separate shipments. If the items can ship together in one box, they generally need to live under the same shipping profile so the system can combine them more accurately. If it still keeps calculating incorrectly, it may be worth contacting Square's customer support at 1-855-700-6000 because they can review how the profiles are currently built and spot where the conflict is happening.
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