404 response

Hi, i’m receiving an error when redirect to MercadoPago:

“Received invalid IPN response from MercadoPago” with 404 error code.

I already checked my MercadoPago configuration (my only doubt was around redirect url and is my website url since i don’t know what should be).

Can you help me?

Thanks in advance!

Notes:
– My wordpress, woocommerce, this plugin are all up to date
– My website is under https (i tried disabling security plugins, and is the same)
– I’m using sandbox.

https://ww.wp.xz.cn/plugins/woocommerce-mercadopago/