PLC OPC-UA 64-bit integer mapping

I am using a Siemens S7-1500 PLC with Ignition version 7.9.6. I have a set of 64-bit integers (Lint in Siemens) which I want to map to 64-bit (Long/int8 in Ignition) tags in Ignition via my PLC OPC-UA server.

If I simply drag the Lint (64-bit) OPC tag from the Ignition OPC browser into the Tag browser it registers as a 32-bit tag. If I do the same with a Dint (32-bit) in the PLC this correctly maps into Ignition as an int4.

Has anyone encountered this mapping issue before?