Lost iphone in beach

So we were just standing on the shore of Varkala beach and suddenly a wave came which just pushed us down and the iphone fell out of my pocket and immediately it was gone. We waited, searched, came again to the spot but didn't find anything. What should I do? Any chance I can get back the dead phone even? It happened around 4:30 to 5pm. What next steps should I take? Tried calling phone but out of network(obviously!), can't see any location on iCloud> find my device.

It's really distressing and spoiled my trip. Please share your opinions, suggestions and comments.