Warning The security token did not match. The request was aborted to p

Everytime I turn on system cache, login by mod_SCLogin always show,

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Warning
The security token did not match. The request was aborted to prevent any security breach. Please try again.
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but the origin joomla login or turn off system cache, it works fine, can you help?

I turn the sclogin Module cache off, it works good now. Thank you, it is a very good software.