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you cannot place an order more than two points above the previous sell/buy even if the next sell is heaps above that. this is whilst the SP is under 10c. Increasing the SP by a margin larger than 2 points (0.2 cents in this case) is considered manipulation. You can increase by a larger margin (0.5 - 1c I believe) when the SP is over 10c. Conversely you can sell down at as low a level as you like and they don't care. nice isn't it. You need to step buy to get to the current offer. put in multiple buys of small amounts until you get to the sell order. You may see this quite often.