Upgrade my instance amazon ec2

how can i upgrade my ec2 instance
-my version is 12 SP 1
-when i run command zypper in zypper-migration-plugin i found this error

Refreshing service ‘Web_and_Scripting_Module_x86_64’.
Problem retrieving the repository index file for service ‘Web_and_Scripting_Module_x86_64’:
Medium not attached: plugin:/susecloud?cookies=0&credentials=Web_and_Scripting_Module_x86_64&path=/services/1153

Check if the URI is valid and accessible.
Refreshing service ‘cloud_update’.
Download (curl) error for ‘ftp://rtmshdhl/x86_64/sles12-sp2-ga/repodata/repomd.xml’:
Error code: Connection failed
Error message: Could not resolve host: rtmshdhl

Abort, retry, ignore? [a/r/i/? shows all options] (a):

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