FYI to all, bottles are not intended to seal via the threads (re the teflon tape advice), the top of the cap itself either seats into the top of the neck of the bottle, or against the top face of the rim. Leaks are generally due to the cap seal being nicked, or a burr on the interior of the top of the inner rim of the bottle, or top face of the rim. If there is no burs, dents, splits, etc in the rim of the bottle, replacing the cap should stop the leak.
The other thing, that appears to be one of the round coke bottles, but the cap looks to be from a smart water bottle or similar. Is it possible you have a cap/bottle mismatch, and returning the proper cap to the bottle would fix it?
That might be the easy fix attempt, go buy a bottle of coke, and stick the cap on that bottle, and see if it still leaks.