Which variable do I need

Hi guys new to the forum, xfeeder and my first post.
I have a trigger for HiLo that only lays after (x) losses, which works fine. I also have in the same trigger a back on card three providing there have been(x)wins for that card.

The calculation for the back is easy its an even £2 per bet. It is the lay stake that is proving difficult to achieve.

When the back bet loses it is supposed to recover the back bet loss, and it does sometimes.
I am using last_lost+2.06 but what I found is if there is say £4.00 already lost and the back bet wins then last lost becomes zero and the £4.00 is forgotten about.

What variable will remember total lost (thats whats been lost below the starting bank) since the session started.

What I am looking for is accept the win from the back bet but do not forget when the lay bet is triggered to recoup the £4.00 from the above example.

Thanks in advance

Added 2nd Oct
27 views and no answers, perhaps I did not explain myself properly
What I want the lay bet to calculate the total lost disregarding the last back win. The reason is the last back win does not recover the lost amount.
Say I had a balance of £100 and had 4 losing back bets therefore @ £2.00 per bet a total lost of £8
Then the 5th back bet wins giving me a £1.50 profit for that 5th bet. I am still £6.50 behind and need to remember that when the lay trigger kicks in. But using last_lost does not work as that would now be 0.
I tried total_pl but that only shows the total profit loss which is not correct either. Works fine if total p/l is below zero but I am looking for a variable that only shows the losses that have not been recovered even when the funds balance shows a profit, say I have won £200 so far then apply my scenario, to still show the £6.50 deficit.