@Akshay I understand you are trying to use "Ubuntu Desktop 22.04 LTS" under Marketplace images for your Lab plan.
Unfortunately, Azure Lab Services does not currently support creating labs with non-Standard images that requires a purchase/plan information. Sometimes it does not necessarily mean it costs money, for example BYOL images are "free" but still require plan information.
At this time, you can choose one of the images with Standard terms (accepted) status or create and use your own image in Azure compute gallery.
The Lab Services team is working to include these images in the future, unfortunately I am not able to provide an ETA for when they would be available.
Please let me know if you have any further questions or need further assistance.
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