I have two files where two classes are defined:

First class:

 const { TournamentParticipationDataAccessService } = require('./TournamentParticipationDataAccessService.js')
 const { TournamentDateUtil } = require('./TournamentDateUtil.js')
 const tournamentParticipationDataAccessService =  require('./TournamentParticipationDataAccessService.js')

class TournamentDataAccessService {


 constructor() {
    
    this.tournamentParticipationDataAccessService = new 
    TournamentParticipationDataAccessService()
 } 

 scheduleBeginOfTournament(tournamentObject) {

    var beginningDate = TournamentDateUtil.convertUTCDateToLocalDate(new Date(tournamentObject.beginningDate));

    console.log("Beginning date of tournament: " + tournamentObject.objectID + " " + beginningDate)

    var beginOfRoundScheduler = scheduler.scheduleJob(beginningDate, function() {
        this.tournamentParticipationDataAccessService.checkIfTournamentHasReachedParticipationNumber(tournamentObject) // DOESN'T WORK
    }) 
 }

..

Then I have this other files containing another class from which I want to use a function in my TournamentDataAccessService class

class TournamentParticipationDataAccessService {

...
 checkIfTournamentHasReachedParticipationNumber(tournamentObject) {

    ...
 }
}
module.exports.TournamentParticipationDataAccessService = 
TournamentParticipationDataAccessService
module.exports.identifyWinnerOfRound = this.identifyWinnerOfRound
module.exports.checkIfTournamentHasReachedParticipationNumber = 
this.checkIfTournamentHasReachedParticipationNumber
module.exports.assignParticipantsToGroups = this.assignParticipantsToGroups

why can't I call a function like this.tournamentParticipationDataAccessService.checkIfTournamentHasReachedParticipationNumber(tournamentObject)?