Did you terraform? If not, the rivers that are on the highest level of cliff that you can reach should have clifftop fish in them. If you terraformed, it might have caused the game to not consider them the right body of water.
Have you time traveled at all? If so, perhaps you're not in the right day/time for the fish that you want.
Are you catching any of the more common clifftop fish, or none at all? Are you saying that you're not catching river fish, period, and only pond fish? A clifftop river will have a waterfall leading to a lower level.
If everything is set up correctly, then you'll just be at the mercy of RNG. Some of the clifftop fish are ridiculously rare. If you're able to catch other clifftop fish, then everything is set up right, and you'll just have to keep fishing until you get lucky.
There's been other discussion on the subject of clifftop fish here. I don't know if it will add anything, but it might be worth a look.
what am i doing wrong because this fish just will not spawn. i have fish bait coming out of my ears its right now january 17, 2021 in my game at 8:00pm ive just tried to get them to spawn on dec 17, 2021 at 5-6am and got nothing im in the northern hemisphere. im trying to catch it from the...
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