Welcome to the forum.
Check the antenna area for missing components. They are easy to rip off and have been causing short range issues for a few users.
Test your Arduino with your smart phone. You should be able to keep an active connection for many meters. Just connect with a generic BLE app and then walk slowly away.
Here is a link to a post from a long time ago with some tests I did reply #9 and a picture of the antenna area reply #18.
https://forum.arduino.cc/t/ble-very-weak-signal/631751/9
Well your mobile phone is a lot more expensive. So, hopefully engineers spend some more time and effort on the antenna design to make BLE work even better.