I have an ipad air2, i am unable to to close apps completely after swiping up from bottom and stopping inthe middle to show me I have 6 apps running.in background, when i swipe up to make them disappear nothing happens

If you are unable to force-close Apps from the App Switcher page, perform a forced-restart of your iPad - as this will often clear an isolated software issue:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

You are very welcome 🙂