Thank you,
Gary

That's a common failure point for this style operator. The way the handle is held in place is with a small metal collar inside the hole. When that strips out, there isn't really much that will hold the handle in place. It will be loose at best, and at worst, it will simply fall out.
If you need a short term solution, you can use scotch tape to pad out the handle stem. That will give it a little extra thickness to allow for a more "snug" fit in the hole. This will let you continue to use the operator for quite some time, but ultimately it's only temporary.
Eventually you will need to replace the operator and handle entirely. The products suggested above are the modern equivalents to this older style setup.