PHP 8.1 Syntax

I'm getting the following error:

 PHP Fatal error:  Array and string offset access syntax with curly braces is no longer supported in /var/www/html/recursos_ativas/vendor/symfony/validator/Symfony/Component/Validator/Util/PropertyPath.php on line 41

It's a syntax error, the curly braces is no longer supported. 

Some idea to solves it easily?

Thanks and regards