File Upload: It's not possible to use device's camera if Take Photo widget is in the form.

3. After the above error, the camera changes to attach file option, which shows an option of camera but when we use camera, it shows an error.

Different browsers and different devices have varying levels of access to different parts of the device. Mobile Chrome and Mobile FireFox tend to work best, but there are still many settings both in the browser and in the device that can deny or allow varying levels of access.

Generally, if the form is going to be used on mobile, I would recommend using a regular file upload field and having the user take the photo first, then upload through the field.  This prevents any issues with accessing the camera or camera storage.

The correct answer to this user's question is that the Take Photo widget has been broken for a month and there are many of us that would love an update as to when it will be working again.

https://www.jotform.com/answers/1192054/

The issue in the thread you referenced is different from the current users.  As soon as we have further information regarding the issue in the thread you referenced, we will update that thread.