There is space between tub spout and fiberglass

My upstairs bathtub/shower is fiberglass. This is the kids bathroom; they must have hit or grabbed the tub spout and shifted it a bit. I recently noticed that there is now a space where the spout comes out of the fiberglass; in other words, the tub spout no longer sits flush against the back fiberglass wall. In fact, there is probably about 3/8" open space at the underside of the spout and a more narrow space on top.

Since this is an upstairs bathroom, I am concerned that water may splash back behind the tub and ruin the ceiling below.

Right now, I am trying to keep the crack filled with plumbers putty.
Is the plumber's putty a reasonable solution? Or does this sound like I need a plumber? Maybe a new tub spout?

Our fixtures are Delta brand; I can't find a screw or anyway to tighten the spout.

Thanks in advance for your help!

Usually, those that are slip-on have a set screw; those that don't are screwed onto a threaded fitting. If you unthreaded one that far, it would leak around the fitting. It sounds like the pipe may not have been screwed or anchored well in the wall and somebody pulled on it, bending the pipe.