Actually, the ZBDongle-E is the newer model, but, I’ve had better experience with the older ZBDongle-P.
Still at a distance of only a few feet there shouldn’t be an issue with the E. First thing would be to check for zigbee/wifi channel conflicts, @hedda’s interference primer covers that and more.
If that fails get the Dongle-P or other CC2652P based stick and report back. Willing to bet it will perform better, but still could be spotty if there are interference issues.