Q: can not get Garage Band on my ipone 5c for free

When did you buy your iPhone? If GarageBand is free will depend on the Purchase date, see this link:

Free Apple apps for your iPhone, iPad, and iPod touch with iOS 8

To get GarageBand for free, you need a device that was activated or purchased

on or after September 1, 2014

Where are you looking?

Have you tried this? 

1. Open the App Store.
2. Tap "Apps Made by Apple" under "Quick Links".
3. Tap Download All, or you can download apps one at a time.

Give Apple Support a call. Your iPhone may have a wrong purchase date. Then only Apple sort this out.