Errores en checkout eligiendo Mercadoenvios como shipping

Hola! esta ma?ana agregué a las opciones de shipping la integracion con mercado envios, anduvo super bien. Pero luego no se que ocurrio que comenzo a fallar, probe borrando el plugin (hasta como carpeta dentro del servidor) y reinstalarlo pero sigo teniendo el mismo problema. Me da numerosos errores en checkout.

No se si es que justo estan haciendo actualizaciones, o se me rompio algo a mi.
Gracias!

Uncaught ReferenceError: require is not defined
    at backbone.min.js?ver=1.2.3:1
    at backbone.min.js?ver=1.2.3:1
notes-common-v2.js?ver=6.2.1-201826:32 Uncaught ReferenceError: Backbone is not defined
    at notes-common-v2.js?ver=6.2.1-201826:32
    at notes-common-v2.js?ver=6.2.1-201826:158
admin-bar-v2.js?ver=6.2.1-201826:2 Uncaught ReferenceError: _ is not defined
    at admin-bar-v2.js?ver=6.2.1-201826:2
plugins-full.js:22 Uncaught ReferenceError: module is not defined
    at plugins-full.js:22
    at plugins-full.js:22
app.js:1 https://bunnny.co/shop/wp-content/themes/la-zyra/assets/js/plugins/min/jquery.vc_row_parallax.js
api.mercadopago.com/modules/tracking/checkout?token=1382131767148045&referer=https%3A//bunnny.co:1 Failed to load resource: the server responded with a status of 500 ()
api.mercadopago.com/modules/tracking/checkout?public_key=APP_USR-129987d8-88b2-4ad4-9b03-b5b3149f68d6&referer=https%3A//bunnny.co:1 Failed to load resource: the server responded with a status of 500 ()
checkout.min.js?ver=3.4.3:1 Uncaught TypeError: Cannot read property 'length' of null
    at HTMLSelectElement.<anonymous> (checkout.min.js?ver=3.4.3:1)
    at Function.each (jquery.js?ver=1.12.4:2)
    at a.fn.init.each (jquery.js?ver=1.12.4:2)
    at Object.success (checkout.min.js?ver=3.4.3:1)
    at i (jquery.js?ver=1.12.4:2)
    at Object.fireWith [as resolveWith] (jquery.js?ver=1.12.4:2)
    at y (jquery.js?ver=1.12.4:4)
    at XMLHttpRequest.c (jquery.js?ver=1.12.4:4)

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