If you see a screen that looks like this (click here) then the Clave is not valid. Review your Fideicomiso and ensure you have the correct Clave Catastral.
Reading the statement
Ensure your personal items are correct. If you just purchased the property you may see details for the previous owner. This is because the registration process is not complete. You MUST still pay the taxes as the Key is assigned to your property. Having a different name makes no difference to the tax department.
Base Catastral (Registry Base): This is the registered property value in Pesos. Jurisdictions in the US and Canada re-assess property values on an annual basis. In Los Cabos, the major re-assessment happens when a property is sold. In between property sales, the tax office updates the value periodically based on inflation or other indices.
For example this is the change in Base Catastral for our home: