It is true. Real Madrid performance is very unstable, it will be difficult to expect them to win both La Liga or UCL now. Real Madrid has complicated problem in every line. They have fragile defense, they have weak midfield and attacking line as well. Honestly, I don't expect much on Real Madrid to win UCL with this bad performance. I only hope that Real Madrid can return to the 1st place in La Liga standings. However, they must improve their game style and teamwork. They also need to have better creativity in attacking. I can't believe that Real Madrid has bad accuracy in shooting although they have many popular attackers.
In the next few weeks when they win connective matches, you will say that their midfield is strong 
I think Valverde and Bellingham's absence hurt them a bit and also the fact the Ancelotti doesn't seem to give enough game time for the back-up players. As soon as he took out Mbappé for Endric who has barely played any games this season. I knew it was game over.