Faulty product, failed repair, and now ignoring me
I bought a YUKA mini 800 directly from Mammotion on 31 March 2025 for £1,049 (Order M5483UK). For the first eleven months it worked well. The problems started in early March 2026. Both navigation lenses developed internal misting and moisture, causing the unit to stop repeatedly and falsely detect obstacles that weren't there. Mammotion support's initial advice was to use a hairdryer and store the unit indoors. Neither worked. I returned the unit for repair on 24 March 2026 and it came back on 12 April with the entire top section (camera and sensors) replaced — visibly brand new, factory seals still over the lenses. After approximately one week of normal operation in standard British spring conditions (10–15°C, no extreme weather), the identical fault recurred. The brand-new lenses had misted internally. I emailed Mammotion on 23 April with photographic evidence, suggesting that as the same fault had appeared on what is effectively a re-built machine, the unit is inherently defective and should be replaced. Mammotion replied on 24 April stating the matter was being "taken very seriously" and would be escalated to their service centre and an evaluation team. That was the last substantive contact I have had from them. Three follow-up emails (27, 28 and 29 April) went unanswered. A 30-minute live chat on 29 April produced another assurance that I would hear back "very soon." Nothing followed. On 1 May I sent a formal Letter Before Action under the Consumer Rights Act 2015, addressed to Mammotion Technik GmbH's registered Managing Director in Düsseldorf and copied to support, PR, marketing and privacy teams. It exercised my final right to reject the goods under Section 24 and gave a seven-day deadline for a substantive response. Seven days have passed. No response of any kind. I am now proceeding with a Mastercard chargeback through my card issuer and a Trading Standards referral via Citizens Advice. I'm leaving this review so prospective buyers can weigh the product's engineering against the company's apparent inability to resolve a documented inherent fault. When the product works it's good. When it doesn't, and the issue can't be closed with an apology and a complimentary set of blades, expect to be ignored. I will update this review if and when Mammotion engages.