Not able to Sign Digitally using Digital ID

[#1]

A document required Digital signature, which is in pdf. While I open the document using Adobe Reader X, the document says "Document cannot be saved, can be printed after filling"

I have created a Digital ID, but when I click the signing area, nothing is popping up. 

How to solve this issue? Thank you in advance.

[#2]

A document required Digital signature, which is in pdf. While I open the document using Adobe Reader X, the document says "Document cannot be saved, can be printed after filling"

I have created a Digital ID, but when I click the signing area, nothing is popping up. 

How to solve this issue? Thank you in advance.