Hi Duc,
You can use the following support portal link to replace MX UI certificate.
https://support.imperva.com/s/document-item?bundleId=z-kb-articles-km&topicId=989c86be.html&_LANG=enus
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Cezmi Cal
technical support engineer
Barikat Internet Guvenligi Bilisim Ticaret A.S.
Ankara
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