All of a sudden the Gazebo is not loading the model

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Everything was working all of a sudden the below error shows up :

[ INFO] [1636693505.721342602]: Finished loading Gazebo ROS API Plugin. terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::lock_error> >' terminate called recursively what(): boost: mutex lock failed in pthread_mutex_lock: Invalid argument

When I restarted my PC the above-mentioned error went away but the gazebo is unable to load the models which was happening earlier before the error which I mentioned occurred.