Hi @elzabe,
I understand you are trying to download an app that you previously deleted from your iPhone 6. It sounds like you are able to download other free apps, but just not this one in particular.
Which app are you trying to download?
Your profile shows you have the latest version of iOS, so that's a good start.
The next thing I would suggest is to restart your iPhone. That will re-establish a connection to the internet.
You may have deleted the app off of your iPhone, but you would not have deleted it from your Purchases, so try following the steps to redownload it.
Download your past purchases
You can redownload apps on your iPhone or iPod touch, iPad, Mac or PC, or Apple TV (4th generation). You can also redownload some in-app purchases.
- Open the App Store app.
- On an iPhone or iPod touch: Tap Updates, then tap Purchased.
On an iPad: Tap Purchased.
- Find the app that you want to download, then tap the Download icon
. After the app downloads, you can open it from your Home screen.
Enjoy the rest of your day!