Backup failure help

New install, FreePBX 10.13.66-19, Asterisk 13.14.0

Three other FreePBX servers are successfully backing up to the same FTP server without issue. This one is failing. It appears to be trying to overwrite an existing folder in the FTP root. There are no backups from this system in the root or in the folder. I’ve confirmed the credentials and triple-checked that the settings match the other two servers (which are on the same FreePBX and Asterisk version). The only difference is that the backup job was built on older versions of FreePBX on the two functional servers.

Error:
Initializing Backup 2
Backup Lock acquired!
Running pre-backup hooks…
Adding items…
Building manifest…
Creating backup…
Storing backup…
Saving file to remote ftp
Whoops\Exception\ErrorException: ftp_put(): Cannot create a file when that file already exists. in file /var/www/html/admin/modules/backup/vendor/touki/ftp/lib/Touki/FTP/FTPWrapper.php on line 153
Stack trace:

  1. Whoops\Exception\ErrorException->() /var/www/html/admin/modules/backup/vendor/touki/ftp/lib/Touki/FTP/FTPWrapper.php:153
  2. Whoops\Run->handleError() :0
  3. ftp_put() /var/www/html/admin/modules/backup/vendor/touki/ftp/lib/Touki/FTP/FTPWrapper.php:153
  4. Touki\FTP\FTPWrapper->put() /var/www/html/admin/modules/backup/vendor/touki/ftp/lib/Touki/FTP/Uploader/FileUploader.php:92
  5. Touki\FTP\Uploader\FileUploader->upload() /var/www/html/admin/modules/backup/vendor/touki/ftp/lib/Touki/FTP/FTP.php:217
  6. Touki\FTP\FTP->upload() /var/www/html/admin/modules/backup/functions.inc/class.backup.php:487
  7. FreePBX\modules\Backup\Backup->store_backup() /var/www/html/admin/modules/backup/bin/backup.php:143

The FTP log:
2017-05-10 23:53:41 10.141.1.251 - 10.141.1.254 21 ControlChannelOpened - - 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 - 10.141.1.254 21 USER obfuscate\freepbxbackup 331 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 PASS *** 230 0 0 9458447c-b75e-4f50-97a8-bb2128f164da /
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 TYPE A 200 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 PORT 10,141,1,251,178,109 200 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 20 DataChannelOpened - - 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 20 DataChannelClosed - - 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 LIST / 226 0 0 9458447c-b75e-4f50-97a8-bb2128f164da /
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 TYPE I 200 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 PORT 10,141,1,251,167,178 200 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 20 DataChannelOpened - - 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 20 DataChannelClosed - - 183 18 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 STOR /Portland/20170510-165223-1494460343-13.0.191.11-1441389131.tgz 550 183 18 9458447c-b75e-4f50-97a8-bb2128f164da /Portland/20170510-165223-1494460343-13.0.191.11-1441389131.tgz
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 QUIT - 221 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -
2017-05-10 23:53:41 10.141.1.251 obfuscate\freepbxbackup 10.141.1.254 21 ControlChannelClosed - - 0 0 9458447c-b75e-4f50-97a8-bb2128f164da -

Any ideas appreciated.