Can anyone please give comments to solution of correct error while open Product Form of ODOO 12?

Error:

Uncaught TypeError: Cannot read property 'string' of undefined

http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1638

Traceback:

TypeError: Cannot read property 'string' of undefined

    at Class._renderTagLabel (http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1638:660)

    at Class._renderInnerGroupLabel (http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1629:105)

    at http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1626:114

    at Function._.each._.forEach (http://192.168.31.95:8069/web/content/835-5861f27/web.assets_common.js:12:558)

    at Class._renderInnerGroup (http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1623:63)

    at Class._renderTagGroup (http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1637:228)

    at Class._renderNode [as _super] (http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1629:246)

    at Class._renderNode (http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:2881:50)

    at Class._renderNode (http://192.168.31.95:8069/web/content/835-5861f27/web.assets_common.js:3541:371)

    at http://192.168.31.95:8069/web/content/901-a808bb4/web.assets_backend.js:1634:17