Hi Sadekin,
Welcome to Apple Support Communities. Since this happens with AirDrop between your iPhone and your iPad, make sure the following requirements from How to use AirDrop on your iPhone or iPad - Apple Support are met.
Before you begin
• Make sure that the person you're sending to is nearby and within Bluetooth and Wi-Fi range.
• Check that you and the person you're sending to have Wi-Fi and Bluetooth turned on. If either of you have Personal Hotspot on, turn it off.
• Check if the person you're sending to has their AirDrop set to receive from Contacts Only. If they do, and you're in their Contacts, they need to have your Apple ID's email address or mobile number in your contact card for AirDrop to work.
If you've checked that all the above are true and this continues, try AirDropping to another device from either your iPhone or iPad if possible. Does the same occur? That will help isolate this a bit.
Kind regards.