Hi guys , i do some trading with a trading bot that i developed myself.
For example

Step 1 Placing Limit order to buy 1 coin for 10 EUR
When that order from Step 1 is filled go to Step 2

Step 2 Placing Limit order to sell that coin for 10.10 EUR (10 cent profit)
When that order is willed we have 10 cents profit.


What i noticed...

For example my Available EUR Balance is 25 Euro before all steps.

Step 1 , buying 1 coin for 10 EUR..... Availablce balance 15 EUR, Great!
Step 2 , selling 1 coin for 10.10 EUR....Available balance should be 25.10 (10 cents profit) but its not!!! Its 25.07 (7 cents profit)

Limit orders as i know are with 0% fees right? Then whats happening???
I also see my filled orders and it says FEE:0.00

Thanks