You are sharing a web map or web layer that contains an unsupported Arcade or VBScript label expression.
Arcade label expressions are supported by ArcGIS Online and ArcGIS Enterprise 10.5 and later versions. VBScript field names are supported by all portals; however, label expressions are not supported.
The <value> parameter specifies either an Arcade or a VBScript expression.
Change the expression type.
Hover over the analyzer message. Click the Options button that appears and click Open Label Class Pane. Change the Language to Arcade and create the expression in Arcade. (This solution assumes you are sharing to a portal that supports Arcade expressions.)
Change your caching option to Cache locally.
This solution applies if you use Arcade label expressions and are sharing a tile layer to an older portal.
Labels with expressions will be dropped.