I have spent HOURS trying to figure out why the "group" button wasn't showing when I wanted to group some objects. This video solved my problem. MANY THANKS!!
Open the document and ensure you enable editing then select the group ensure its the group selected because the issue could be you only selecting one shape of the group. The right click preferably on the far corner of the selected group the go for the option group/Ungroup. Let me know if you winning. Regards.
Next time you make video presentation first you need to check your voice and adjust the volume of your speaker to a maximum level before starting your job