Console-- : typeError: uniformMap[mu.name] is not a function

CesiumJS
1 
`Preformatted text`An error occurred while rendering.  Rendering has stopped.
TypeError: uniformMap[mu.name] is not a function
TypeError: uniformMap[mu.name] is not a function
    at ShaderProgram._setUniforms (http://localhost:4200/src_app_pages_main_main_module_ts.js:146446:37)
    at continueDraw (http://localhost:4200/src_app_pages_main_main_module_ts.js:141225:17)
    at Context.draw (http://localhost:4200/src_app_pages_main_main_module_ts.js:141267:3)
    at DrawCommand.execute (http://localhost:4200/src_app_pages_main_main_module_ts.js:142935:11)
    at PostProcessStage.execute (http://localhost:4200/src_app_pages_main_main_module_ts.js:249313:17)
    at execute (http://localhost:4200/src_app_pages_main_main_module_ts.js:250011:11)
    at PostProcessStageCollection.execute (http://localhost:4200/src_app_pages_main_main_module_ts.js:250072:5)
    at Scene.resolveFramebuffers (http://localhost:4200/src_app_pages_main_main_module_ts.js:262439:17)
    at render (http://localhost:4200/src_app_pages_main_main_module_ts.js:262703:9)
    at tryAndCatchError (http://localhost:4200/src_app_pages_main_main_module_ts.js:262716:5)

Iam trying Viewshed,but getting this above error, Can Anyone help to resolve this issue.