Unable to display IEEE1722-1 packet in Wireshark 3.0.3

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Would be easier to help if you could provide a capture.

The capture on the right of your image is IEEE 1722 over Ethernet. The capture on the left is IEEE 1722 over UDP, on ports 27221 and 37221. The default UDP port for IEEE 1722 is 17220 and the dissector does not provide a preference to change that, nor does it provide a "Decode As..." option.

If the data actually is IEEE 1722 then your options seem to be:

• Recompile Wireshark setting the dissector port to be those used in your capture.
• Modify your capture to use port 17220, e.g. by using a tool such as TraceWrangler.

However, that might not be required. It seems the data in the capture on the left might be encapsulated Ethernet\IEEE 1722 can you try right-clicking the "data" item, choose "Decode As..." and then in the column named "Current" choose "Ethernet" from the droplist.