Hello Kaushal Pathak
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
For the first issue, it is important to ensure that the Azure VM agent is installed on the migrated VMs. If the machine is running version 9.7.0.0 or later of the Site Recovery Mobility service, the Azure VM agent is automatically installed by the Mobility service on Windows VMs. On earlier versions of the Mobility service, you'll install the agent manually. If you're running a version of the Site Recovery mobility service earlier than 9.7.0.0, or you have some other need to install the agent manually, you can download the VM Agent installer and run the installer file.
For the second issue, it is important to ensure that the Azure VM agent is installed on the migrated VMs. If the VM is migrated without the required changes, the VM may not boot, or you may not have connectivity to the migrated VM. You can try to install the VM agent manually on the affected VM. If the issue persists, you can try to boot the VM in safe mode and check if the VM agent is running. If it is not, try to start the service manually. If the issue still persists, you can try to uninstall and reinstall the VM agent.
If you have tried all the above steps and still facing the same issue, it is recommended to contact Azure support for further assistance.
Hope that helps.