Fill and Sign Greyed Out

[Miranda33438219c4qz]

I've searched through the posts for this and none seem to have an answer that I can follow.

I have downloaded a document which requires a signature at the bottom, the file allows me to click in the box and type but the fill and sign yourself in adobe pro is greyed out.

I've checked the security settings of the file and there are no restrictions on signing, and I also can't sign by going to tools>use a certificate> digitally sign. I need to sign these regularly so printing and signing is a huge waste of time. 

[Abambo]

Is there a possibility to share that document?

[Miranda33438219c4qz]

I cannot share my version because it is filled in with personal details, but the form is from the ATO. Found here: ATO Objection form - For Tax Professionals I have tried to re-download the form to see if it was just my copy of the form and even the form directly downloaded has the same problem.