How can i access an external domain's api using bearer token ?

I'm trying to access another domain's api from my serrver using ajax post request but there's a handicap this request sending by my pc's external ip adress and there's a firewall rule my server's ip adress has been set so when i'm trying to access that api with below code part it throws me an 403 error. Am i using wrong solution by using ajax or is there a better solution for this situation?

$.ajax({
            url: 'domain.com',
            type: 'POST',
            
            data: {
                'user':'user',
                'pass':'pass'
            },
            crossDomain:true,
            dataType : 'jsonp',
            beforeSend: function (xhr) {
                xhr.setRequestHeader('Authorization', 'Bearer Token');
            },
            success: function (res) {
                console.log(JSON.stringify(res));
             },
            error: function (res) { 
                console.log(JSON.stringify(res));
            },
        });