javascript - Uncaught TypeError: this.handleSearchNext is not a function

Question

I am attempting to override a keyEvent for a handsontable. The code runs but will get the error "Uncaught TypeError: this.handleSearchNext is not a function" But it is a function defined, so I'm not sure why I am getting this error.

async componentWillReceiveProps(newProps) {
    this.hotTable.updateSettings({
      afterDocumentKeyDown(e) {
        if (e.key === 'Enter') {
          this.handleSearchNext(e)
          e.stopPropagation()
          console.log('Stopped propigation in table', e)
        }
      }
    })
}
.
.
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handleSearchNext = (e) => {...}