Issue in urdu RTL language

I am usinig Open Journal Systems3.1.2.0

I am using Urdu RTL language in Subtitle of the article title which is a requirement for my journal.
When I upgrade the urdu language changes to ??? Questions marks

Please guide any possible solution. I cant find any

Hi @a2usmani,

The version of OJS that you’re using is no longer supported by PKP. I recommend that you upgrade to the newest version of OJS, as it is possible that your issue will be resolved by upgrading. However, other community members may wish to offer assistance.

Upgrading instructions are available in the PKP Administrator’s Guide.

Information about the latest version of OJS can be found on the PKP Website

PKP Team

Yes Thats is why I am asking becuase it needs upgrade. I am trying to upgrade but having some issues. Please see the following thread and please help

I have been trying so upgrade since a year but not getting results. Please help

The same issue is going on with version too.