Whenever I try to update a firestore document in flutter flow with a field that is a list of custom data type, it does not go through and often crashes the build giving me the "build failed" screen. However, I can still add an array of maps in my firestore collection with dummy data and read/ display in flutterflow. In my case I have a collection called "songlists" with fields of name: string, and songs: array of maps. In flutter flow the scheme is set as name: string, and songs: <List(Data Type: Song)>. The song custom data type just has string and integer fields. No matter what I try, either no songs are being updated in firestore, or I get the "build failed" screen with no output in the console.
Note: the songlist field of (name: string) read and writes to firestore with no problem.
Note: The FF project is dependent on another deployed library FF project where these schemes and data types are created. I am also trying to create a document on button press, and also testing with component/page state variables populated with values, and with unpopulated values.