Can't run app in build/test mode due to "Error: The getter 'lineColor' isn't defined for the class 'FlutterFlowTheme'"

Attempted to try and open the build mode and later test mode, but both fail due to this code error:

Target dart2js failed: ProcessException: Process exited abnormally with exit code 1:

lib/user_info/user_info_widget.dart:178:59:

Error: The getter 'lineColor' isn't defined for the class 'FlutterFlowTheme'.

- 'FlutterFlowTheme' is from 'package:test/flutter_flow/flutter_flow_theme.dart' ('lib/flutter_flow/flutter_flow_theme.dart').

color: FlutterFlowTheme.of(context).lineColor,

^^^^^^^^^

Error: Compilation failed.

#0 RunResult.throwException (package:flutter_tools/src/base/process.dart:122:5)

Error: Failed to compile application for the Web.

I am a first time user with no coding experience, so asking for help on how to solve this problem.