First question is why did you replace the RD? The circumstances might help identify the root cause.
Second is the RD a direct part# replacement or a different model / part# ? What did you have and with is the new one?
Third question is describe "not shifting properly." By trying to describe a consistent and repeatable symptom you may actually discover the problem. (Bonus points!)
After all of that, adjusting a RD is a methodical approach, no magic, did you follow a process from the Park Tool website or other step-by-step instructions? Other potential problems are bent hanger and less likely chain issues.
Go back to your bike, put it in a stand or flip it over, and step through the shifting then describe what you see.
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