lilkrissPL,
Thanks for trying those steps out. Do you happen to have any other Bluetooth accessories you could try pairing to the same iPhone? That could help to see if the issue is with the AirPods specifically, or all Bluetooth accessories.
Which iOS version is currently installed? You can check for any pending updates in Settings > General > Software Update. If you need to update, follow the steps here, including backing up ahead of time: Update your iPhone, iPad, or iPod touch
Also try toggling Bluetooth off and back on in Settings > Bluetooth (not Control Center). Additionally, try removing the case, if you use one. Try to also turn off Wi-Fi in Settings > Wi-Fi (not Control Center). These can help to further rule out interference.
Cheers.