ninja: error: 'devel/lib/libgflags.so', needed by 'devel/lib/libgflags_catkin.so', missing and no known rule to make it

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Hi everyone, I'm trying to build my project in ubuntu 18.04 (ROS Melodic). The issue I'm facing at the moment is that my project builds just fine in terminal using catkin_make, but when I use vscode and cmake to build, I get this error. This is the whole error message that I get:

[main] Building folder: src 
[build] Starting build
[proc] Executing command: /usr/bin/cmake --build /home/user/catkin_ws_test/src/build --config Debug --target all -j 10 --
[build] ninja: error: 'devel/lib/libgflags.so', needed by 'devel/lib/libgflags_catkin.so', missing and no known rule to make it
[build] Build finished with exit code 1

Whats wrong here and how should I go about it?