I'll try to explain this situation.
When trying to trade with low liquidity tokens. It's usual to find wide spreads.
For example, I want to sell a token and the buying price is 30 satoshis and selling price is 20 satoshis.
I put a limited order to sell at 29, now the spread is between 20-29 and my order is the first.
The key point is the exchange historial. Here appears some finished trades at 25 satoshis.
And I say: OMG, this was not on the order book...
Then change my order to 25 satoshis, now the spread is 20-25.
Some trades appears at 22 satoshis.
Look like tricky!
Finally I decided to close the spread. Putted my order at 21 satoshis, now we are with 20-21 satoshis spread.
And... at this point no more operations happens in the market.
Is this a bot? Is this the exchange trying to cheat users?
Thanks for your help!
Edit: it happened me in few medium-small exchanges.