Latest smartthings multisensors

Two queations
when I remove the battery from the latest smartthings multisensor the magnet is no longer attracted to the sensor body, is this normal

I have two of the new smartthings multisensors both have gone offline at the same time I have tried to re pair them and reset both but neither of them show the green or red lights I have changed the cr2450’s and no difference

? #1 yes, normal

?#2 a cpl comments, if they were previously paired successfully, you would need to exclude them prior to repairing. That is needed in this case.
If these are the same 2 sensors you just changed the batteries, my bet is you have a weak zigbee mesh network.

suggestions. Reset the sensor (paperclip). Improve your network by adding repeaters, rebuild the mesh network after adding repeaters.

All of the above can be researched by searching this forum. And/or YouTube etc

When I first got them the led’s would flash and no longer do, they have been excluded and the batteries have been replaced