It is all about the location you buy your from. There are many sellers online. game market aren't trustworthy in particular in the case of delivering gold. They may steal your money and then disappear or offer fake gold that disappears within a couple of hours of playing.
The most effective way to avoid being banned from RuneScape is to purchase OSRS gold in a safe manner from trusted sellers. RSorder ensures that the currency is authentic and delivered within the timeframe they specify through their customer service or live chat agent. Trustworthy sellers guarantee your OSRS gold you purchase from them is authentic that is, you may use the gold within the game to purchase additional items.