Why does my Gujarati sound so 'hard' compared to my cousins?

I’m a heritage speaker who understands most of what’s said at family dinners, but whenever I try to reply, I struggle with the retroflex consonants (like the difference between ટ and ત). My cousins tell me I sound like I’m reading from a book rather than just talking. How can I stop over-emphasizing those sounds to sound more like a native speaker from Ahmedabad?