Script to modify lot size of pending order

Hello dear programmers/guests,

I know there is similar thread/script described but there is a lot threads and I´m confused to find it. It would be great if someone could make me one script or just post here .

How should it work: when set any pending order then order adjust to "x" % (for example 2% and with stop loss 15pips) of balance account

real example:
account balance: 5000
risk ratio % : 2%
stop loss: 15 pips (150 points)
pair: EUR/USD

result: 0.827 lot

Thank you if someone response

As far as I know, you can't modify the size of an existing pending order
It would have to be replaced by a new order

thanks for response,

yes I was afraid of this situation, I wrote it not very clear because of my bad english, I will try to write it more clearly

imagine this situation, pair EUR/USD: you have 5000€ balance, 1% stop loss(SL=12pips=0.517 lots), but we win= profit 1% of balance (50€) (R:R=1:1)
2nd trade: now our balance is 5050€ 1% stop loss (SL=12pips=0.522 lots) again win and we earn 50.50€
3rd trade: balance 5100.50€ stop loss 1% stop loss (SL=12pips=0.527 lots)


see these differences between lot sizes per trade? and this I want to automate and find any script on it

If still not clear let me know I will try more

EDIT: I open new trade only by pending orders