Adding to winners

In an earlier post with the same topic I was told that this is called box trading however when i googled it, the results were confusing so i will try to clear up what i was trying to get at in the original post, I'm not a native speaker, sorry for that.

Hopefully this clears it up:

What TSX does: https://www.tradingview.com/x/vOkogzbT/#

What i would like to have: https://www.tradingview.com/x/qMp8JzGB/

I'm not trying to hedge, i just want to be able to add to my winners without the second trade having the stop loss at the first trades SL.

This works fine on ninja trader, is it really not allowed? If so, i apologize.