I contacted the seller and they said this was normal. I do not think this is normal for a battery to degrade this quickly. Afterwhich, I have had no more responses back to my questions about this product. So this is why I am posting this to make others aware.
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In some cases, the nature of the item means that it is non-returnable, for example, due to hygiene/health and personal care/wellness/consumable nature of the product. In some circumstances, these items may be eligible for a refund or a replacement (for example, if you receive the wrong item due to an Amazon AU error or if the item is faulty). Please Contact Us and see About Items That Can’t Be Returned.
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To return faulty items see our Returning Faulty Items policy.
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More details: About Our Returns Policies