No puedo clonar mi web con wp staging... sale error

lo he intentado hasta 3 veces siempre se para en el 2% y sale este error:

Thank you for using WP Staging
WP Staging is ready to create a staging site!

1Overview2Scanning3Cloning
Copy database tables
Copy files
2%
Replace Links
Reset Display working log
Fail
Fatal Error: This should not happen but is most often caused by other plugins. Try first the option "Optimizer" in WP Staging->Settings and try again. If this does not help, enable wordpress debug mode to find out which plugin is causing this:
504 Gateway Time-out

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