Hello,
Quick question: do you have any corals in the tank?
If not, just turn off the lights (or set it to very low intensity or just keep room light) and let the tank like this for some time.
Meanwhile, it is not a bad idea to add any live rock from another mature tank.
If you don’t have corals there is no need to start all over in my option… and if you have, send it back to your local fish store for some time.
Use the next months to let the tank stabilise and also to see if the parameters starts to settle in a reasonable range. And if not, add another piece of live rock… and check it again.
That’s the fun/challenge of the hobby!
Best of luck!