The Preview action is a available for some quotes, but not for others.
SAP Cloud for Customer
The option for the preview action is only visible if the ConfirmationIssueingStatus is not initial.
The Business Configuration Fine Tuning for the document type may have been changed between the creation of both documents.
If that is the case, it is possible that one object has business variant types external pricing AND direct customer acceptance for which no printing - and thus no preview - is offered.
In contrast, the other quote may have exclusively the business variant for external pricing (and not direct customer acceptance as this was switched off in-between) and therefore allows printing and a preview.
Please check the setup of your document/ transaction type and decide which scenario you want to have
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