Website down after upgrading WordPress

Hello,

after updating my WordPress Version to the newest one, my website doesnt work anymore.
I also cant log in to the admin panel. There comes the same issue.

I installed a BackUp Plugin, but after uploading the file with SQLAdmin, there comes again the same error message.

“Fatal error: Cannot redeclare update_termmeta_cache() (previously declared in /kunden/378590_76889/webseiten/schloessl2/wp-includes/taxonomy.php:1356) in /kunden/378590_76889/webseiten/schloessl2/wp-content/plugins/custom-taxonomy-sort/includes/simple-term-meta.php on line 95”

I am actually pretty sure i did the backup BEFORE updating wordpress so I have absolutely no idea how I can fix it now with a broken backup file.

Thanks for your help!

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