savefig(FIGhandle, fullfile(destdirectory_FIG, 'name_of_FIG.fig'));
You can also use saveas, though it's maybe better suited to save other formats (together with print). Maybe then the issue is with the \directories/ (hence the fullfile above). Remember to use openfig in Matlab (also drag and drop works) or even saveas with the formattype option'm' or 'mfig' (Save the figure as a MATLAB figure file and additionally create a MATLAB file that opens the figure).