[Q] Lost knox when root topic

'm a newbie here so sorry if it is very stupid question.
I have just rooted my device and I found that I can't enter the knox mode anymore.
I have stored some files in knox mode and forgot to move it out.
Is there anyway to restore these files? If it can't, can I delete all of them because these files are heavy - which are 6 GBs.
I prefer deleting these files 'cause of they're too large.
Thanks for your help. I really appreciate it.