Yes . I think you have a 57 ah nominal pack that is not lifepo4. Or something even less capacity, but claimed to be 60 ah.
Cheapo cell in it, would mean no way they put out the nominal capacity in real use. Best guess,, you may have a 50 ah pack.. possibly less depending on how many shitty cells are in there.
This is pretty much normal for cheap packs,, and I'm assuming you did not pay $2000 for this one. The cells may be the ones listed above, but in the cheaper pack price range, they could be b grades, fakes, or just cheap cells, whatever. Over stating capacity is not unusual in china. So you might just have 2 ah cells, making it in fact a 40 ah pack.
Nothing much you can do about it now,, you can't legally mail it back to china get a refund. You can put a watt meter on it, and prove how low capacity it is, then complain, possibly get some of your cash refunded.
Mostly,, I think likely you got what you paid for,, (But not what they said it would be, 60 AH) it's just not lifepo4, and that's why it seems way to light and small. In that size,,you don't want lifepo4 anyway.
