promise returned this.handleSubmitUpdate is ignored

I am using material-table editable table with react js. Data is coming on the table. I have Edit, Save, Cancel buttons.

When I click the Save button, the records I normally update are not updated. On reactjs, I get the error "promised returned is ignored" and it doesn't run the code.

it doesn't seem to run the update code.

import React, { Component, useState } from "react";
import withAuth from "../../components/helpers/withAuth";
import AlertMessageBox from "../../components/helpers/AlertMessageBox";
import { connect } from "react-redux";
import { Button, Col, Row, Table, Input } from "reactstrap";
import MaterialTable, { MTableEditRow } from "material-table";
import icons from '@material-ui/core/Icon';
import Edit from '@material-ui/icons/Edit';


 class Bounty extends Component {
   constructor(props) {
     super(props);
     this.domain = process.env.REACT_APP_APISERVER;
     this.state = {
    isLoaded: true,

  drBounty: [],


  columns: [
    { title: 'Adı', field: 'doctorName',
      cellStyle:{padding: "1px", whiteSpace: "nowrap", overflow: "hidden", textOverflow: "ellipsis", maxWidth: "1px"},
      editComponent: (props) => (
        <Input
          type="text"
          //autoFocus={true}
          //margin={"dense"}
          required={true}
          placeholder={"Doktor adı"}
          defaultValue={props.value}
          name={"doctorName"}
          variant="outlined"
          onChange={e => { props.onChange(e.target.value) }}
        />
      )
    },

    { title: 'Soyadı', field: 'doctorLastName',
      cellStyle:{padding: "1px", whiteSpace: "nowrap", overflow: "hidden", textOverflow: "ellipsis", maxWidth: "5px"},
      editComponent: (props) => (
        <Input
          type={"text"}
          required={true}
          placeholder={"Doktor soyadı"}
          defaultValue={props.value}
          name={"doctorLastName"}
          variant="outlined"
          onChange={e => { props.onChange(e.target.value) }}
        />
      )
    }]

     };

     this.getBountyList = this.getBountyList.bind(this);
 }



  async getBountyList(id) {
    await fetch(`${this.domain}/api/bounty/list?groupCode=${this.props.account_profile.profile.profile.groupCode}&doctor=${id}`,{
  headers: {
    Authorization: `Bearer ${localStorage.getItem("id_token")}`,
    "Content-Type": "application/json"
  }
})
  .then(res => {
    console.log(res);
    if (res.ok) {
      return res.json();
    } else {
      return res.json().then(err => Promise.reject(err));
    }
  })
  .then(json => {
    //console.log(json)
  })
  .catch(error => {
    //console.log(error);
    return error;
  });
 }

 async handleSubmitUpdate(data) {
   console.log(data)

   await fetch(`${this.domain}/api/bounty/update/` + data.id, {
    method: "PUT",
    headers: {
      Authorization: `Bearer ${localStorage.getItem("id_token")}`,
       "Content-Type": "application/json"
    },
  body: JSON.stringify({
    user: this.props.account_profile.profile.profile.id,
    doctorName: data.doctorName,
    doctorLastName: data.doctorLastName,

  })
})
  .then(response => {
    console.log(response);

    if (response.ok === true) {
    }
    return response.json();
  })
  .then(json => {
    console.log(json);
    }
  })
  .catch(err => {
    console.log(err);
  });
   }


 render() {
    const { isLoaded, drList } = this.state;

    const isRowUpdating = (rowData, status) => {
      rowData.tableData.editing = status ? "update" : undefined;
      this.forceUpdate();
    };

  if (!isLoaded) {
    return <div>Loading...</div>;
 } else {
  return (
    <div className={"animated fadeIn "}>

      <Row>

        <MaterialTable
          Icons={icons}
          title={"Bounty List"}
          style={{height: "50", width: "50"}}
          columns={ this.state.columns }
          data={ this.state.drBounty }

          actions={[
            rowData => ({
              icon: Edit,
              tooltip: "Edit",
              onClick: (event, rowData) => {
                isRowUpdating(rowData, true);

                this.setState({
                  id: rowData.id,
                  doctorName: rowData.doctorName,
                  doctorLastName: rowData.doctorLastName
                });

              }
            })
          ]}

          components={{
            EditRow: props => {

              const newRowData = {
                ...props.data,
                id:  props.data.id,
                doctorName: props.data.doctorName,
                doctorLastName: props.data.doctorLastName,
              };

              return (
                <MTableEditRow
                  {...props}
                  data={newRowData}
                  onEditingCanceled={(mode, rowData) => {
                    isRowUpdating(rowData, false);
                  }}
                  onEditingApproved={(mode, newData, oldRowData) => {
                    isRowUpdating(props.data, false);


                        this.handleSubmitUpdate(newData);


                  }}
                />
              );
            }
          }}
        />
      </Row>
      </div>
    );
  }
  }  
 }


 export default connect(withAuth( Bounty ));