Change request.comment-value? - mql4

Question

I use different kinds of stop losses and would like to be notified (SendNotification()) about which kind of stop loss was hit upon trade exit.
Let's say I entered a trade by...
request.action = TRADE_ACTION_DEAL;
request.symbol = pSymbol;
request.type = pType;
request.sl = pStop;
request.tp = pProfit;
request.comment = pComment;
request.volume = pVolume;
request.price = SymbolInfoDouble(pSymbol,SYMBOL_ASK);
request.price = SymbolInfoDouble(pSymbol,SYMBOL_BID)
OrderSend(request,result);
I would now like to have the request.comment changed by the last stop loss like so:
request.action = TRADE_ACTION_SLTP;
request.symbol = pSymbol;
request.sl = pStop;
request.tp = pProfit;
request.comment = "Fixed SL";
PositionSelect(_Symbol);
request.order = PositionGetInteger(POSITION_IDENTIFIER);
OrderSend(request,result);
Unfortunately the second block of code does not change the first request.comment = pComment; though (instead the new comment is [sl 1.19724]).
Is it possible to change the comment via TRADE_ACTION_SLTP? What am I doing wrong?
Thank you!

Answer 1

I would now like to have the request.comment changed
There was never a way to do this in MQL4/5 trading platforms
Sad, but true.
The core-functionality was always focused on engineering a fast, reliable soft-real-time ( providing still just a best-effort scheduling alongside the stream of externally injected FxMarket-Event-Flow ), so bear with the product as-is.
Plus, there was always one more degree-of-uncertainty, the Broker-side automation was almost free for modifying the .comment-part of the Trade-position, so even if your OrderSend() was explicit on what ought be stored there, the result was unsure and the Broker-side could ( whenever, be it immediately or at any later stage ) change this field outside of any control ( which was not left on your side ), so the only semi-UUID# keys could have been placed into the .magic ( and your local-side application code always had to do all the job via some key:value storage extension to the otherwise uncertain Broker-side content.
Even the Trade number ( ID, ticket ) identifier is not always a persistent key and may change under some Trade management operations, so be indeed very carefull, before deciding your way.
like to be notified ( SendNotification() ) about which kind of stop loss was hit upon trade exit.
Doable, yet one will need to build all the middleware-logic on one's own :
The wish is clear and doable. Given a proper layer of middleware-logic will get built, one can enjoy whatever such automation.
Having built things like an augmented-visual-trading, remote AI/ML-quant-predictors or real-time fully-adaptive non-blocking GUI-quant-tools augmentations ( your trader gets online graphical visual aids inside GUI, automatically overlaid over other EA + Indicator tools on the GUI-surface, fully click-and-modify interactive / adaptive for fast visually augmented discretionary modifications of the traded asset management ), so only one's imagination and resources available are one's limit here.
Yet, one has to respect the published platform limits - the same as OrderModify() does not provide any means for the wish above, the add-on traded assets customer-specific reporting on position terminations is to be assembled by one's own initiative, as the platform does not provide ( for obvious reasons noted above ) any tools, relevant for such non-core activity.