You should not use surface elements unless you are modeling concrete shear walls. For all other types of structural entities, you should use plates. So I would suggest using a mesh of plates for your case. Coming to this specific error, it may be due to the fact that the nodes that you have used in the surface incidence are not in a single plane. However we need to take a look at the .std file to understand what is causing the error. The part you uploaded is from the output file.
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