尝试分配字段时，Laravel Eloquent过滤器出现问题

I need to use filters to generate a collection with Laravel. I have a Project model which has many Investments. I make a query and retrieve a collection at the $projects variable. Then, there is a collection inside each one of the $projects collection called investments. I need to retrieve only the projects which have investments such that:

$investments->status = 'paid' && $investments->user_id is contained in $users_list

I used two nested filters, one for the projects collection and another one for the investments collection. I use the inner investments collection to filter by status and user_id and assign the filtered collection to $filtered_investments. Then I try to modify the unfiltered investments collection inside each project collection and replace it by $filtered_investments, however that does not happen. The investments filter works well but $filtered_projects contains its original investments collection instead the one I calculated.

Is there a way to do this? Thanks!

    $projects = Project::has('investments')
            ->with('investments')
            ->get();

    $users_list = [54];
    $investment_status = 'paid';

    $filtered_projects = $projects->filter(function($proj_value,$proj_key) use ($users_list,$investment_status){

        // Calculate the filtered_investments collection checking the status and user_id fields
        $filtered_investments = $proj_value->investments->filter(function($inv_value,$inv_key) use ($users_list,$investment_status){
            $return = $inv_value->status == $investment_status && in_array($inv_value->user_id,$users_list);
            return $return;
        });

        // Here I have a new filtered_investments collection which I want to assign to
        // the current project investments field. 
        $proj_value->investments = $filtered_investments;

        // This is only to return the current project if there is at least one
        // element inside $filtered_investments
        return $filtered_investments->count() > 0;
    });