Fatal errors in settings

Hello. I can’t setup images and change text.

The text prints an error:

Fatal error: Uncaught Error: Undefined constant "O"
in .../wp-content/plugins/next-watermark/includes/nwm-functions.php on line 40

Call stack:

    nxtwm_GetRomanYear()
    wp-content/plugins/next-watermark/includes/nwm-acp-page.php:259
    require()
    wp-content/plugins/next-watermark/includes/nwm-functions.php:223
    nwm_acp_callback()
    wp-includes/class-wp-hook.php:307
    WP_Hook::apply_filters()
    wp-includes/class-wp-hook.php:331
    WP_Hook::do_action()
    wp-includes/plugin.php:476
    do_action()
    wp-admin/admin.php:259

Image settings:

Fatal error: Uncaught Error: Path cannot be empty
in .../wp-content/plugins/next-watermark/includes/nwm-acp-page.php on line 479

Call stack:

    getimagesize()
    wp-content/plugins/next-watermark/includes/nwm-acp-page.php:479
    require()
    wp-content/plugins/next-watermark/includes/nwm-functions.php:223
    nwm_acp_callback()
    wp-includes/class-wp-hook.php:307
    WP_Hook::apply_filters()
    wp-includes/class-wp-hook.php:331
    WP_Hook::do_action()
    wp-includes/plugin.php:476
    do_action()
    wp-admin/admin.php:25

I deactivated all plugins and set the theme to basic, didn’t help.

WP version 6.0.1
PHP version 8.0.21