I have check system landscape settings it's correct.
I am not sure it was working before or you are creating contract first time, better could you please check the below config.
IMG > SRM > SRM Server > Technical Basic Settings > Define System landscape, local and RFC flags should be selected for SRM & ECC RFC's while configuring the system connections.
Also please check the BBP_LOCAMAP table whether the plants are replicated to SRM or not for which you are creating contract and check the Org. structure extended attributes tab and make sure that the locations are maintained.
All checks you said are maintain, but still error persist.