Airdrop not working on New iPad and older version

I am a IT Tech we have bought several new iPads this year to change out some of the older models. But the AirDrop is not working on them. It will see the older iPad but will not receive any of the files being sent. We have update to the new iPad Pro's from the iPad Air from 2 years ago. Both models are up to date. But something is causing them not to communicate. We have checked the settings and both are set up correctly.