Functions that automate complex process are not usually going to be set up for wild deviations from the typical situation. You are using a function that is trying to equate all loadings, etc., across groups, but you don't estimate the same loadings across groups because you don't'have all the same indicators across groups. You will need to test invariance manually by adding constraints directly in the model syntax for the variables that are shared across groups, in the form of using the same label for parameters that should be equal. For example, to test whether loading invariance fits as well as "configural invariance" (only loosely defined in this context, since you can't possibly fit the same pattern of fixed/free loadings across groups that have different variables), you can compare these two models: