You can’t really use two forms that share the same fields on a single page. If these have different <form> wrappers then you either need to put up with the errors or put the forms on different pages. If they share a <form> wrapper then the forms will not work and you’ll update both posts with the values in the second occurrence of the fields. The other choice is to create two identical field groups and use one of them for each of the forms.
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