I’m new using figma, and I was doing a design with multiple lines and shapes, when I tried merging all the objects with flatten, most of those objects seem to dissapear, or become invisible, I was doing this because I wanted to use a gradient, they are all in a group and I flattened them in different layers so none dissapear, but the gradient option is still not letting me move the gradient because I have multiple objects.

How can I merge all those layers so I can apply a gradient and move the gradient around?

Sorry If it’s confusing, I’ll answer any questions. Thank you!