public with sharing class AccountingPeriodCreationService  {

public static List <AcctSeed__Accounting_Period__c> accountingPeriod;
public static Date currentDate;
public static Date firstDayOfCurrentMonth;
public static Date lastDayOfCurrentMonth;

public void createdAPLogic(){
    accountingPeriod = new List <AcctSeed__Accounting_Period__c>();
    currentDate = Date.today();
    firstDayOfCurrentMonth = currentDate.toStartofMonth();
    lastDayOfCurrentMonth = currentDate.addMonths(1).toStartofMonth().addDays(-1);


    List<AcctSeed__Accounting_Period__c> checkAccountingPeriodAlreadyExist = [SELECT Id, AcctSeed__Start_Date__c, AcctSeed__End_Date__c FROM AcctSeed__Accounting_Period__c where AcctSeed__Start_Date__c = :firstDayOfCurrentMonth];

        if(checkAccountingPeriodAlreadyExist.isEmpty()){
            accountingPeriod.add(
                new AcctSeed__Accounting_Period__c(
                Name = 'Name',
                AcctSeed__Status__c = 'Status',
                AcctSeed__Start_Date__c = firstDayOfCurrentMonth,
                AcctSeed__End_Date__c = lastDayOfCurrentMonth
                )
            );
        }
   }
}

global with sharing class CreateAccountingPeriods implements Schedulable {
/**
 * @description Executes the scheduled Apex job.
 * @param sc contains the job ID
 */

global void execute(SchedulableContext sc) {
    //Non static method cannot be referenced from a static context
     AccountingPeriodCreationService apc = new AccountingPeriodCreationService();
    String sch = '0 1 0 1 1/1 ? *';
    String jobID = system.schedule('Create Accounting Period', sch, apc);
   }


}