After bringing in Alexander-Arnold, Real Madrid have also been linked with Stuttgart player Angelo Stiller, this effort is still related to Madrid's plan to increase the strength of its defense, in the last 2 seasons Angelo Stiller has been one of Stuttgart's most prominent players that's why Real Madrid and Liverpool are eyeing him. Reportedly Real Madrid are most interested in him but until now there is no certainty, I suspect the transfer fee is the problem. The combination of Angelo Stiller and Alexander-Arnold might be the right choice along with their reputation at their previous club, Madrid must move faster to sign him.
But why do Stuttgart want to sell Angelo Stiller after they extended his contract in January. Stiller is a good defender, and he was very active in his defensive position last season before Stuttgart lost out of form this season. I think that Real Madrid will still finalize his signing if truly they need him and i don't think that his transfer fee will be a problem for them. Since Alexander Arnold has already joined the team, it would be good to sign another center back who will assist him in the defense. Even if Madrid succeeds in solidifying their defense by signing Angelo Stiller, they will still need to sign another defender as a reserve in case any player among Stiller or Alexander Arnold gets injury.