Not able to login after URL change

I have domainA.com and i have changed that to domainB.com from phpmyadmin,i have also changed the correct root path.I am able to access the domainB.com without issue but when i try to login using domainB.com/wp-admin my login details are not working.I have tried many suggestions from this forum without success.Can you please help what i can check to fix this issue