In the movie Avengers: Endgame Captain America will solve everything when it comes to the Infinity Stones. He brings them back to their own time and place, so that everything can continue as it is. But Cap doesn’t seem to have done one thing right.
You will probably remember that the 2012 Space Stone was originally targeted. But the attempt to steal that stone failed, so Tony and Cap traveled back to Camp Leigh in 1970 to get it. The Screen Rant site points out that something has probably gone wrong here.
Loki, of course, escaped with the Space Stone after the heist failed in 2012. Every other new reality that emerged from the removal of the Infinity Stones was restored when Captain America brought back the six Infinity Stones. But he probably forgot that in 2012 Loki managed to escape with the Tesseract.
When the 2012 Loki picked up the Tesseract in the lobby of the Stark Tower, he immediately disappeared into a portal. Even if the 2019 Captain America knew how to find the 2012 Loki, it seems unlikely that he would have found it. That also means immediately that the new Loki timeline has not been repaired.
The brothers Anthony in Joe Russo have already said that this would lead to a complex situation. “Steve was supposed to restore all previous timelines to when the stones disappeared. But Loki, when he teleported away with the Time Stone, would make his own timeline. It would be very complex, because it would be impossible for Cap to reset the timeline unless he finds Loki. So when Loki takes the Space Stone away, he creates an alternate reality. “
And that seems to be the story of the series that Marvel is currently developing for the series Loki which can be seen on Disney +.