Stanley 1913 Flask Defect – Tea Goes Cold in 2 Hours

I bought a 1-litre Stanley 1913 Classic Legendary cranberry flask from Amazon.co.uk on 5 August 2025 and, despite only having used it a handful of times, it is not keeping drinks hot as expected. The exterior becomes hot to the touch shortly after I pour in boiling tea, which suggests a problem with the insulation, and the tea went almost cold within about two hours during a recent picnic. To be sure, I tested the flask again at home and experienced the same issue, even though the product has no dents, marks, or visible damage and has been stored carefully. I also own a larger Stanley flask, which performs very well, so I can clearly see that this particular 1-litre cranberry flask is not working properly in comparison. Since the flask appears to be faulty despite very light use and careful handling, I request a replacement of the same model. I would appreciate support in resolving this issue under the product’s warranty or quality guarantee.