Issue with UploadSetwithTable - Unsupported Media Type (415) in RAP (S/4HANA Public Cloud)

[Cebin]

Hello SAP Experts,

I am working on a RAP-based application in S/4HANA Public Cloud where I need to attach multiple files and upload them using the UploadSetwithTable control.

However, I am encountering the following error during upload:

Error Response:

{
"message": "The server is refusing to process the request because the entity has an unsupported format"
}

HTTP Status: 415 (Unsupported Media Type)

Implementation Details:-

My Fragment code: 

<core:FragmentDefinition xmlns="sap.m" xmlns:core="sap.ui.core"

    xmlns:f="sap.f" xmlns:upload="sap.m.upload">

    <Dialog id="uploadDialog" title="Upload File" draggable="true" resizable="true" contentWidth="50%" contentHeight="50%">

        <content>

            <Table id="table-uploadSet"

                inset="true"

                autoPopinMode="true"

                hiddenInPopin="None"

                items="{path: 'attachmentModel>/Attachment', templateShareable: false}">

                <headerToolbar>

                    <OverflowToolbar>

                        <Title text="Documents" level="H2" />

                        <ToolbarSpacer />

                        <ToolbarSeparator />

                        <upload:ActionsPlaceholder id="uploadButton" placeholderFor="UploadButtonPlaceholder" />

                    </OverflowToolbar>

                </headerToolbar>

                <dependents>

                    <plugins.UploadSetwithTable

                        id="uploadSet"

                        uploadUrl="/path"

                        multiple="true"

                        beforeUploadStarts=".onBeforeUploadStarts"

                        uploadCompleted=".onUploadCompleted"

                        cloudFilePickerEnabled="true"

                        actions="uploadButton">

                        <rowConfiguration>

                            <upload.UploadItemConfiguration

                                fileNamePath="Filename"

                                mediaTypePath="Mimetype"

                                urlPath="url"

                                previewablePath="previewable"

                                fileSizePath="fileSize"

                                isTrustedSourcePath="trustedSource"/>

                        </rowConfiguration>

                    </plugins.UploadSetwithTable>

                </dependents>

                <columns>

                    <Column id="fileName" importance="High">

                        <header>

                            <Label text="File Name" />

                        </header>

                    </Column>

                    <Column id="actionButton" importance="High" />

                </columns>  

                <items>

                    <ColumnListItem>

                        <cells>

                            <Text text="{attachmentModel>Filename}" />

                            <Button type="Transparent" icon="sap-icon://decline" press="onRemoveHandler"/>

                        </cells>

                    </ColumnListItem>

                </items>

            </Table>

        </content>

        <endButton>

            <Button text="Close" type="Transparent" press="onCloseFileUploadDialog"/>

        </endButton>

    </Dialog>

</core:FragmentDefinition>

Controller code: 

onBeforeUploadStarts: function (oEvent) {

            var oUploadSet = oEvent.getSource();           

            var oItem = oEvent.getParameter("item"); // Get the item inside mParameters

            var oModel = this.getView().getModel("zmm_sd_pr_atch");

            var csrfToken = oModel.getHttpHeaders()["X-CSRF-Token"];

            var sContentType = oItem.getMediaType() || "application/octet-stream";

            oItem.addHeaderField(

                new sap.ui.core.Item({ key: "x-csrf-token", text: csrfToken })

            );

            oItem.addHeaderField(

                new sap.ui.core.Item({ key: "slug", text: oItem.getFileName() })

            );

            oItem.addHeaderField(

                new sap.ui.core.Item({ key: "Content-Type", text: sContentType  })

            );

},

onUploadCompleted: function (oEvent) {

            var iResponseStatus = oEvent.getParameter("status");

            if (iResponseStatus === 201) {  // Check if upload is successful

                this.getView().getModel("zmm_sd_pr_atch").refresh(true);

                MessageToast.show("Document Added Successfully");

            } else {

                MessageToast.show("File upload failed.");

            }

        },

Any guidance on proper request formatting would be greatly appreciated!

Thanks in advance!