Q: Problems to print my book

I have made a book of 26 pages with photos and text, but I cannot order the book, since the menu " buy the book" remains in grey.

2 pages have a warning sign, but I don't understand why. One is with one photo and a column of text. The sign is on the left nearby the photo. I changed this photo with different ones, but the problem  remains. On the page with only text, I see the same warning sign. I reduced the text, but the sign remains.

This book is for my best friend's birthday and I can't buy it. Can anyone help me, in France or anywher else.

Thanks

Marie-Claude