Why do some Pages files have a different icon and won't open automatically?

Hello everyone,

Some of my Pages files seem to have a different icon than the regular one: this icon features an orange pen and the words Pages in capitals. Unlike all the other Pages files, they won't open automatically and I am forced to take a longer route and follow the "Open with Pages" routine.

Unlike the orange pen-featuring icon, most of my regular icons in most of my Pages files feature a rectangular leaf-like symbol filled with tiny lines of text.

Is there any way to fix this problem?

I enclose and image of two files - one opens automatically when I click on it while the other forces me to use the "open with Pages" routine.

Thanks in advance for your kindness and help.

Below, there are images of the both icons.