Unexpected Application Error!

Cannot read properties of undefined (reading 'push')

TypeError: Cannot read properties of undefined (reading 'push')
    at https://www.digitalbook.io/static/js/834.747ee2e2.chunk.js:2:36498
    at f (https://www.digitalbook.io/static/js/834.747ee2e2.chunk.js:2:28277)
    at Generator.<anonymous> (https://www.digitalbook.io/static/js/834.747ee2e2.chunk.js:2:29614)
    at Generator.next (https://www.digitalbook.io/static/js/834.747ee2e2.chunk.js:2:28640)
    at v (https://www.digitalbook.io/static/js/834.747ee2e2.chunk.js:2:35289)
    at a (https://www.digitalbook.io/static/js/834.747ee2e2.chunk.js:2:35492)