Pagination stoped working

Hi guys,
We have a really old solution using Prismic and recently upgraded to 7.3.
During that time (we think) pagination stopped working...

It doesn't matter what kind of page variable we pass, it still returns the wrong documents (Always the first document(s)).

However, the strange thing is that everything except the result seems right in the response. Have a look at the bottom to see that the searchquery is correct but the page is wrong.

Any ideas?

Passing this:
$api = Api::get("");
$response = $api->query(Predicates::at('document.type', 'blog-post'), ['pageSize' => 2, 'page' => 2]);

[page:Prismic\Response:private] => 1
[resultsPerPage:Prismic\Response:private] => 2
[resultsSize:Prismic\Response:private] => 2
[totalResultsSize:Prismic\Response:private] => 76
[totalPages:Prismic\Response:private] => 38
[nextPage:Prismic\Response:private] =>[[%3Ad+%3D+at(document.type%2C+"blog-post")]]&page=2&pageSize=2
[prevPage:Prismic\Response:private] => ) 1

A post was merged into an existing topic: PHP-SDK Guzzle is running old version