BACnet Object ID Not Scanning

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Hi

I have a situation where: Server A can discover all devices but on certain devices although the devices scans, the device information does not appear. The devices are on a mstp network and I am doing the bacnet scan on my server which talks to the devices via bacnet routers. The devices which have problem scanning are are the same model/make/rev as the ones which scans properly.

However when I use server B to scan the network, all devices scans properly including their device information.

I am wondering what filter should I be using to look at why this is happening?

I am not good at wireshark and hope someone can enlighten me on this.