There may be an issue with your native mobile build config.
Best register a support ticket so support can help you fix the config.
As a not very nice alternative: Close the project, move the nativemobile folder to another location and start the builder. It will start fresh. So this only works if you know how to configure the build again. There is a .config file in the nativemobile folder backup, which is just a JSON file so you can open it in any text editor but preferably a JSON aware tool like VS Code.