Gear Lag issue - Automatic car - Any Trusted Multi-Brand Expert in Hyderabad?

My automatic car has been facing a gear-shift lag. The showroom keeps insisting on replacing the entire system, which is extremely expensive. But I’m not convinced they’ve done proper root-cause analysis - it feels like they’re just following their manual instead of actually diagnosing the issue.

I tried checking with a multi-brand garage, but they said automatic systems are too complex and it’s safer to rely on the showroom. I’m stuck and not sure whom to trust.

Can anyone recommend a genuinely skilled and trustworthy expert in Hyderabad who can properly diagnose the issue and guide me on what actually needs to be fixed?