Thank you for reaching out via the Bose Community.
I am sorry to hear you have had issues answering calls with your SoundSport Free wireless headphones.
I would recommend checking your audio routing settings via the iPhone to ensure Bluetooth headet is enabled.
Settings > General > Accessibility > Touch > Call Audio Routing > set the option to "Bluetooth Headset."
I hope this helps!
Jeff G - Community Support
Feel more. Do more. Be more. Come check out my profile here. New to the community? Check out the Getting Started board. Help others find answers to your questions by clicking on 'Accept as Solution' at the bottom of a reply. If you see a post you like, make sure to give it a thumbs up!