Don't trust these apps just head out & try but turn on S.A mode 5g ,if u are still not getting signals then there is no 5g in ur area ,that's it , same thing happened to me & with Airtel it was showing phone is compatible with 5g or update it . But ...
It doesn't matter you recharged with 1k or 479 the main thing is 5g is in ur city not in ur area ,when it will be available in ur area you will automatically get 5g signals no update is needed for that specially both Airtel & Jio 5g will work just go...