How to map more than 1 term set to a single metadata column in SharePoint Online?

Hi All,

I have a requirement where in, I have to map 2 term sets to a single managed metadata column. If I try to add a term from different term set(which is not mapped with the managed metadata column), the value gets stored as "#" inside the managed metadata column. I am using a document library in SharePoint Online.

Expecting a quick reply on this. Thanks in advance.

 <d:Functionm:type="Collection(SP.Taxonomy.TaxonomyFieldValue)">
            <d:element>
              <d:Label>#</d:Label>
              <d:TermGuid>68f8e8df-fec3-48f2-a3d0-24e7553c4bc5</d:TermGuid>
              <d:WssId m:type="Edm.Int32">33</d:WssId>
            </d:element>
            <d:element>
              <d:Label>#</d:Label>
              <d:TermGuid>fed295f9-5a94-4040-a48f-886a2ce4e4a2</d:TermGuid>
              <d:WssId m:type="Edm.Int32">34</d:WssId>
            </d:element>
            <d:element>
              <d:Label>#</d:Label>
              <d:TermGuid>ca8d69fe-8496-41f1-bcbb-4de3609a4e4f</d:TermGuid>
              <d:WssId m:type="Edm.Int32">30</d:WssId>
            </d:element>
         </d:Function>
      </m:properties>

Regards,

Shreyash