Jenkins NotSerializableException: groovy.json.internal.LazyMap

i am trying to use jenkins pipeline to show API payload, on the ApiUrl1 runs normally without problems, but on the APiURL2 show that error is Error occurred: groovy.json.internal.LazyMap

    final String response = sh(script: """curl -svf --globoff --request GET --header "Authorization: Bearer ${token}" "$apiUrl" """, returnStdout: true).trim()
    // Parse API response
    def jsonSlurper = new groovy.json.JsonSlurper()
    def result = jsonSlurper.parseText(response)
    String testingResponse = result.toString()
    echo testingResponse

    def payload =
    for (def jobTitleList in payload) {
        def jobTitleName = jobTitleList.job_title_id.job_title
        jobTitles << jobTitleName
    //def jobTitles = payload.collect { it.job_title_id.job_title }
    echo "${jobTitles}"
    for (def jobTitleName in jobTitles) {
        String jobTitleString = jobTitleName.toString()
        echo "Job Title : ${jobTitleString}"
        echo apiUrl2
        try {
            echo "Line 87"
            // Execute curl command to fetch data
            final String response2 = sh(script: """https_proxy=http://{proxy}curl -svf --globoff --request GET --header "Authorization: Bearer ${token}" "${apiUrl2}" """, returnStdout: true).trim()
            echo "Line 91"
            // Parse API response
            def result2 = jsonSlurper.parseText(response2)
            String testingResponse2 = result2.toString()
            echo testingResponse2
        } catch (Exception e) {
            echo "Error encountered while fetching data"
            echo "Error message: ${e.message}"
} catch(e) { 
    echo "${e.message}"
    echo "No PIC"

return jobTitles