Fatal error after rename folder

Hello,
I use 16.0.4 and I ewant to rename a folder from “CRM” to “CRM3”, but nc write, he can’t rename.

I see in the log file a fatal error:

OCP\Files\ForbiddenException: Invalid path

/var/www/html/cloud/lib/private/Files/Storage/Wrapper/Wrapper.php - line 277:  OC\Files\Storage\Local->rename("files/Firma/Aktuell2/CRM", "files/Firma/Aktuell2/CRM3")
/var/www/html/cloud/apps/ransomware_protection/lib/StorageWrapper.php - line 275:  OC\Files\Storage\Wrapper\Wrapper->rename("files/Firma/Aktuell2/CRM", "files/Firma/Aktuell2/CRM3")
/var/www/html/cloud/lib/private/Files/View.php - line 813:  OCA\RansomwareProtection\StorageWrapper->rename("files/Firma/Aktuell2/CRM", "files/Firma/Aktuell2/CRM3")
/var/www/html/cloud/apps/dav/lib/Connector/Sabre/Node.php - line 141: OC\Files\View->rename("/Firma/Aktuell2/CRM", "/Firma/Aktuell2/CRM3")
/var/www/html/cloud/3rdparty/sabre/dav/lib/DAV/Tree.php - line 151:  OCA\DAV\Connector\Sabre\Node->setName("CRM3")
/var/www/html/cloud/3rdparty/sabre/dav/lib/DAV/CorePlugin.php - line 642: Sabre\DAV\Tree->move("files/micha ... M", "files/micha ... 3")

<<closure>>
Sabre\DAV\CorePlugin->httpMove(Sabre\HTTP\R ... "}, Sabre\HTTP\Response {})
/var/www/html/cloud/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105:  call_user_func_array([ Sabre\DAV\ ... "], [ Sabre\HTTP ... }])
/var/www/html/cloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 479: Sabre\Event\EventEmitter->emit("method:MOVE", [ Sabre\HTTP ... }])
/var/www/html/cloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 254: Sabre\DAV\Server->invokeMethod(Sabre\HTTP\R ... "}, Sabre\HTTP\Response {})
/var/www/html/cloud/apps/dav/lib/Server.php - line 316: Sabre\DAV\Server->exec()
/var/www/html/cloud/apps/dav/appinfo/v2/remote.php - line 35: OCA\DAV\Server->exec()
/var/www/html/cloud/remote.php - line 163: require_once("/var/www/ht ... p")

What is wrong?
Thank you!