I am doing Modal pushover(MPA) analysis on a steel frame with b31element for beams and columns and S4R shell elements for steel shear wall (3D). To do MPA I first applied deal a live loads in a general static steps, and then used a general Riks step to perform a load-displacement control analysis with a lateral load pattern! however I am experiencing convergence issues in Riks step if I apply dead and live loads first(they are active in general static step and deactive in Riks step)! the structure does not deform in the direction of lateral load pattern and toward the target displacement anymore! it will go into irrelevant deformed shapes! however I need to apply dead and live loads too! if I perform the Riks analysis alone, everything goes well, somehow it seems the Riks step cant find the correct stability path after applying dead and live loads, and LPF growth become very slow and maybe incorrect! I have attached the deformed shape of the structure after progress of Riks step...

Any suggestion on this issue is a great help and is highly appreciated! thank you for your time!