Hi,
If you have exported the files from ACE, you should be able to import them back as well. What format does it show right now? You can covert to the supported format if it is any other than above from link below:
https://www.sslshopper.com/ssl-converter.html
You can also try , crypto export <file name> terminal and then copy that output and paste it in another window using crypto import <filename> and see if that helps.
If the issue persists i would suggest opening a TAC case and let them a have a look over webex.
Hope this helps.
Regards,
Kanwal
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