Unable to sign "signable" pdf. Sign and Fill/certificates don't work. Can still sign other forms.

This is for an application.  I did not make this form myself.  The form must be opened in Adobe Acrobat Reader DC, I cannot do the cloud fill and sign option, this form is not compatible with it.  I have updated to the most recent version of Adobe Acrobat Reader DC.  

I have repaired, uninstalled, reinstalled, tried different computers, and am taking it to my school's IT dept. tomorrow.

I am not sure what else to do.  This is a Navy application form and is due on Friday.  

I need to be able to sign this... If there is any other information I need to provide other than what I wrote and what my pictures show/say, please let me know ASAP.