System doesn´t block the addition of repeated attachments in the Licenses and Certifications section

Summary: On the Skills and Qualifications Page, in the Licenses and Certifications section, the employee needs to add attachments according to the license selected in the License field. However, we need to make the system block the addition of a repeated attachment document in this section. For example, if he selects a certain License, the system must block both the selection of the same license and block the addition of the same attachment. Does anyone know if this is possible?

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