Sendy Error : SignatureDoesNotMatch

error is coming in my sendy panel even after i've changed access key in setting

"Your Sendy installation is unable to get your SES quota from Amazon because the 'Amazon Web Services Credentials' set in Sendy's main Settings are incorrect. You probably did not copy and pasted your IAM credentials fully or properly into the settings. Please re-do Step 5.2 and 5.3 of the Get Started Guide carefully to resolve this error."