Export has stoped bit options

When I export a box would come up and give me an option to export in 32 or 24 etc. The box no longer comes up and I do not know why. This is causing me problems when I try and post  an image onto my instagram and when I try to edit my pictures on my editing package. Does anyone know how to get back the dialogue box so I can choose my ioptions when exporting thanks. I am using Corel draw X7