App mercadolibre REFRESH TOKEN

Hello! I have an app for iphone which less than 20 days ago I had to update the certificates in apple developper and on the server, after they did that work, after 5 days it stopped working. is an app that works with [login to view URL] in which I have to update the token every 6 hours, the app sends me to a link where it updates the token but ahira pulls as it does not find the page and it does not update me and I can not use it. I need to solve this problem thanks