no puedo crear cuadro para firmar digitalmente.

Hi, Tariq,

Well, two possible reasons come to mind. I've checked the translation of Souvik's answer and it's almost incomprehensible in Spanish, so he may not have bothered replying. And, even in English, you guys didn't really provide an answer, but rather ask unrelated questions, which is rather frustrating. Do let me elaborate; I'll try to reply to your questions in the meantime as well: 

I'm using Adobe pro. The provider of my digital ID is the Spanish government and it works just fine. Actually, I did sign the document, but it wouldn't allow me to — as BIDAO said — create a square on the pages of the document with the information of my signature: the "visible signature". And yes, the document does have a "signature panel", as it's called in Spanish. Is that what you meant by "digital signature field"?

So, discarding all the possible issues you guys mentioned, do you have any idea what might be the problem? As BIDAO said, when you click and try to create a rectangle for the "visible signatures", Adobe won't let you and will give you that message: "Click and drag in the area of the document where you want the signature to appear". Which, as BIDAO said, is precisely what we were trying to do!

Even without a video, I do believe the issue is very straightforward. Btw, I've done that step dozens of times, with no problem until yesterday — not that I'm a novice. 

I'm looking forward to hearing about your possible solutions. 

Regards, 

Javi