For one: you're using v 5.7.2 which dates "2017-06-07" : way before your PHP version (8.1.5)
I've found a 5.7.4 but strangely enough has the same date in composer.json yet was released on Jun 01 2021.
That in itself would prevent me from using it.
Spelling is freeware, which means you can use it for free.
On the other hand, it is not open source, which means you cannot change it or publish it in a modified form.
Time flies like an arrow, but fruit flies like a banana.