There seems to a conflict when using Category Tinymce with Content Views Pro. This is to do with the way in which Content Views Pro buffers the WordPress loop and also uses it numerous times within the buffer.
Category Tinymce 5 uses the end_loop hook to automatically insert the bottom description area. As it stands the bottom description shows numerous times when the end_loop hook is called in the buffer.
One way to deal with this issue is to use Category Tinymce 4 and manually add the needed code into your theme file. Preferably this should be in a child theme to prevent the file from being overwritten when your theme is updated.
If you are not confident with making these changes or can not find a suitable place to add the manual code there is the second option. This option involves modifying the code of Category Tinymce 5.
You should change the code at approx line 492 from
add_action( 'loop_end' , 'wordcatins', 1000 );
add_action( 'pt_cv_print_view_style', 'wordcatins', 1000 );
This will then use a Content Views Pro hook to insert the bottom description area.
Don’t forget that if you uninstall Content Views Pro you will need to change this code back to the original in Category Tinymce.