Bests & Worsts Reviews from Amazon

I don't often write reviews, but in this case I felt obligated to in order to warn people of a potential danger. Let me start by saying I had none of the chord disconnecting issues that so many other reviewers had mention. Not once has the chord become unplugged while in use. The heat function is adequate, and the massage is firm but comfortable. Now, to the issue at hand. The massage/heat function does automatically shut off after 15 minutes, but rarely is 15 minutes adequate to provide relief. On my initial use, I probably restarted it and ran it for maybe an hour. After using it, I decided to shower which is when I discovered two blisters on my lower back. Well, it's two days later and the blisters have turned into the two painful sores you see in the photos. I cannot say for certain whether the sores are a direct result of overuse on my part or a dangerous flaw in the massager. The instructions do say not to use the heat function in excess of the initial 15 minute shut off which I did not. Again, I do not know if the fault lies with me for improper use or the manufacturer for faulty equipment. I will attempt to use it again in shorter durations after my wounds have fully healed then post a follow up review. ***Update: I received this email from the seller trying to bribe me into taking down my negative review in exchange for an Amazon gift card. Considering it's been 2 weeks since I suffered an injury using this product and my injury has still not fully healed, I will not be bribed into taking down my negative review. As a matter of principle, I am changing my very generous 3 star review to one star. I have attached a copy of the email from the seller below. Hi, H**** .Lovely day. There is a $30 Amazon gift card . Could you mind to help me to delete your review? If you are willing to delete your review ,I will offer an Amazon gift card worth $30. We will thank you profusely and even find a homeless kitten to hug on your behalf. If you have deleted your review ,please remember telling me, and then I will give you $30 right away when I see your reply. This is your review. https://www.amazon.com/gp/customer-reviews/R3VXJLD7C58VYX/ref=cm_cr_getr_d_rvw_ttl?ie=UTF8&ASIN=B07Q5WHSBD Again,Time really is limited.So this is the last email you will receive from us so we really do hope you can help me. And I hope that you can reply to me as soon as possible. Thank you and please have a lovely day.