Obviously not underwatered. Right? Underwatered flagging typically involves loss of turgidity of the petiole as well as the leaves (leaf stems droop)
Overwatering is possible.
Anytime I see this the 1st question I ask is; at what point of the light cycle is the photo taken. Some plants have a lower DLI than others. They get their fill of light and take a nap. I had 5 plants in a tent and every day a couple hours b4 lights out she would flag like she was overwatered. Took me forever to figure out. I was watering once every 48 hours in Coco. She still drooped b4 lights out. Did not make sense.
Until it did. Only other thing I see is perhaps some clawing that may or not be typical of hitting DLI or overwatering. Hope this gives you something.