Astro-i18next for language not work when deployed to Vercel

I am using astro-i18next for language translations I have created accurate json files & entered data Everything works perfect on Localhost , but the problem is when I ush code to Vercel , it doesn;t work, means its not picking up data from translations json file
rather it just shows keys as text eg. home.banner.heading
I checked everything peroperly - I can even open translation json file with vercel link but Its not rendering
the data from it

Please help me fix this
I think this is some problem with vercel