Error when try to login or logout

Goodmorning i use this plugin for a long time and don’t have any problem.
With the last WordPress update i have that issue, when i try to login give this error:

Fatal error: Cannot redeclare av_early_add_filter() (previously declared in /membri/.dummy/apps/wordpress/wp-content/plugins/altervista/early.php:83) in /membri/.dummy/apps/wordpress/wp-content/plugins/altervista/early.php on line 85
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