A family of Microsoft on-premises document management and storage systems.
Hi @Navas Shereef ,
Is there anything has been changed before the issue occurs? Please follow these steps to troubleshooting this issue:
1.You could try to reset the search index.
2.Per my research, like lots of blogs said you should make sure the value for ‘Allow Multiple Values’ is set as same for the Managed Metadata Site Column and the Managed Property.
3.Did you change the default zone of web application to use HTTPS instead of HTTP? In some cases, they switched site url to HTTPs and the issue was resolved.
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