Issue with Defining Contact Between Concrete and Wall

[sal21]

Hello, I am modeling a building in Abaqus. I will apply shotcrete. I have a concrete slab with reinforcement mesh attached to masonry walls. There are anchors connecting these elements. I defined the interaction between the masonry wall and the concrete as a tie, but the model gives an over-constrained warning. If I define a different interaction, like cohesion, I don't have experimental data. What type of contact should I define?
Thank you.