The supplement game is an unregulated wild west of money making, a buyer beware market, making fraud rampant. Plus there is no science that says taking supplements (aside from B12 and possibly vitamin D) is even useful.
It is also important to know that online sellers like Amazon and Ebay are not responsible if you get a counterfeit product. Brick and mortar stores are. If you are going to take supplements, this might be a case where paying for them at a retail store is your best option.
These are the two articles we referenced in our live this morning (July 23, 2019)