Roland KahlenbergCorrect answer
Legend
June 2, 2022
The Red Error, as it reads, states that you have placed an unrelated property into the Eessential Graphics Panel (EGP). So, only related AND supported AND non-essentialized properties and layers (Replacement Media) are allowed within the EGP. A related property resides either in the Primary Comp in the EGP or in a layer (such as to be used as a Replacement Media) or a property (in a layer) in a comp that's been nested in the Primary Comp of the EGP.
Double check these. If you are absolutely certain you are placing a related property/layer into the EGP then restart AE and give it another go. HTH
Very Advanced After Effects Training | Adaptive & Responsive Toolkits | Intelligent Design Assets (IDAs) | MoGraph Design System DEV
