The option save is disabled from Acrobat Reader and acrobat Pro DC. I cannot use it, now

Hi

I i have lost the option save to use it from my app. And i have not changed anything. I only use the option save as but "save" is disabled from anywhere of my Acrobat workarea

Could  somebody explain me what can be happening to my app Acrobat reader and Acrobat pro DC version? and if you know the solution , could you guide me to fix it? Please . Thanks