Exception in rendering!

Message: Cannot read property 'index' of null

TypeError: Cannot read property 'index' of null
    at <anonymous>:36:859750
    at Array.map (<anonymous>)
    at t.value (<anonymous>:36:859551)
    at t.value (<anonymous>:36:861439)
    at t.value (<anonymous>:36:863376)
    at n (<anonymous>:36:401264)
    at G (<anonymous>:36:401527)
    at e.render (<anonymous>:36:403099)
    at e.read (<anonymous>:36:402835)
    at Object.renderToString (<anonymous>:36:407129)