Suddenly Stopped Ranking

So, basically, we had our website meetecho.io and we were ranking well on Google for ‘Echo AI’ then out of nowhere we drop off the face of the earth on Google. We found it this was most likely due to us sending cold emails from this domain and so we bought a new domain meetecho.app and moved the landing page across to that. We then made meetecho.io a 302 redirect to meetecho.app and for some reason this new meetecho.app isn’t ranking anywhere on ‘Echo AI’ (should be the highest ranking keyword for it) the only place I can see it ranking 1st is ‘Meet echo ai’ even then it’s the old website (meetecho.io) which is ranking there. I’m so confused but wondering if a 302 redirect has brought over the bad rep from the old website as well. Does anyone know a way around this or how to fix? TLDR: Fucked my first domain by cold email, switched to new one with a 302 redirect, still isn’t ranking anywhere. Is this cos of the 302 redirect?