Disaapointed by magneto rechargeable led lantern.

I bought a Magneto recharcheable led lantern last year and the content on the box states that it goes on for 60 hours on a single charge. But mine stays bright for only an hour and thereoff it becomes dim, I cannot read or write when the light is dim. So I don't know what the problem is but I am extremely dissapointed and I cannot even recommend it to anyone. When on charger the red stays on until it's taken off the charger, not even knowing whether it's fully charged or not. I even charged it for 72 hours just to make sure that it's fully charged, but still it only stayed bright for an hour. This is extremely disaapointing.