How do I upgrade INTL & ICU versions? (Prestashop backoffice incompatibility)

Hello everyone, I'm currently not able to log into the admin panel of my prestashop installation which is hosted on my cpanel server. I've read that a common bug is having an outdated intl & icu versions. I wanted to know if there is any way of upgrading this myself, and where to do it. My intl and icu versions : & ICU.PNG">72989 What I see when i try and log into prestashop backoffice : This screen stays stuck like this indefinitely. I can provide more info if necessary.