Amey01, looks like the Mylar is pulling up and away from the bottom seam of the panel. This is not uncommon, and can be addressed at home.
First, verify that the panel is holding its structural integrity by taking it off the speaker and checking that the bonding between front and rear stators is solid and continuous along the bottom of the panel.
Sometimes, the glue along the bottom seam will give and allow the panel ends to separate and lose grip on the membrane. This is usually caused by some stress on the curve of the panel during transport. But can also happen after years of sitting in a hot climate.
While there is no way for a user to re-tension the Mylar, you can at least keep it from getting any worse by coming up with a way to secure the front and rear stators to each other so the Mylar stops being pulled out.
Once you are convinced that the panel has a reasonable grip on the Mylar around its periphery, you can use the hair drier trick to carefully re-tension the Mylar at the bottom of the panel. You want to cause the portion diagonal to the wrinkle to get tighter and straighten the membrane. So a few passes of the heat along the bottom edge of the panel and up to within a few inches if the wrinkle might do it.
I had the exact same size wrinkle in the corner of one of the panels in a Logos center, and the hair drier trick smoothed it out.
Now, none of this is really necessary as long as the sound is still acceptable to you. Yes, it’s sub-optimal, but as a percentage of radiating surfaces, that’s not much to get concerned over.