How to recover trigger

How can I create a trigger that tries to recover 50% of my loss over 3 games and then restarts with default lay/back if it didnt succes recover 

Plz help =)

Plz look at this.

this string is used for recover (back_size + last_lost/last_bet_price) but instead of the last_bet_price  Im looking for a code that can use the current bet price, but i cant find it.

PLZ help.