Hi Ruthirappan,
For a better understanding of the issue you encountered, I would like to confirm some information first:
1. For "if i'm accessing exchange", do you mean that you configure your Office 365 Exchange account in the Mail application or some mail client(such as Outlook for Mac) in your Mac?
2. For "i give correct password it says incorrect password", do you mean that you can use the same username and password to login the Office 365 OWA(https://outlook.office365.com/owa/) without any issues?
3. Do the other users in your organization encounter the same issue?
4. Could you please provide some screenshots about the issue via the Private Message for further analysis?
Any updates are appreciated.
To access the Private Message, please perform the following steps:
1. Go to the Your details section on the right side of the community site.
2. Click the Private Message.
3. Click the subject title of the response to read the message.
Best regards,
Kid Yang