Yes, that seems to indicate either a problem with the network connection strength in that location or with the magnet alignment.
Also, I have read duplicate messages can be a symptom of problems with repeaters, again possibly because of network strength or repeaters that are incompatible with Xiaomi/Aqara products. But you said you are using Trådfri bulbs as repeaters, right? Are you using any other Zigbee devices that are repeaters?
Any interruption in the Zigbee network can lead to Xiaomi/Aqara devices dropping their connection. This is because they don’t follow the standard Zigbee protocol of rejoining the mesh when requested by the hub. That is also the reason for incompatibility with most Zigbee repeater devices, but in conjunction with Xiaomi/Aqara devices not checking in as often as the repeater devices expect.
Did your hub reboot or was there some interruption in the Zigbee network? Also, some kinds of other radio signals in the same frequency range can cause enough interference to disrupt the connections of Zigbee devices - including certain 2.4GHz WiFi channels, cordless phones, etc.
However, regardless of the reason, there is nothing that can be done to change the behavior of Xiaomi/Aqara devices not rejoining the network when requested. So the best way to handle this is to manually rejoin them.
To manually rejoin a Zigbee device, either do what @Jani explained:
or if that doesn’t work, follow the same steps as pairing (“Add a thing” in the mobile app and put the Xiaomi/Aqara device in pairing mode), but still make sure to leave the device in the hub’s device list.
As long as the entry for the device includes the ZigbeeId information:
then the hub should be able to match up the device being rejoined to that device entry. You won’t see it appear in the mobile app ready to rename as you will with a newly paired device, though. It will just be reconnected, and a new Device Network Id will be assigned to it.
