diff --git a/src/rest/APIRequest.js b/src/rest/APIRequest.js
index ae46e28..eb7551c 100644
--- a/src/rest/APIRequest.js
+++ b/src/rest/APIRequest.js
@@ -66,7 +66,7 @@ class APIRequest {
       }
       headers = Object.assign(headers, body.getHeaders());
       // eslint-disable-next-line eqeqeq
-    } else if (this.options.data != null || this.options.usingApplicationJson) {
+    } else if (this.options.data != null) {
       body = this.options.data ? JSON.stringify(this.options.data) : undefined;
       headers['Content-Type'] = 'application/json';
     } else if (this.options.body != null) {
diff --git a/src/structures/DMChannel.js b/src/structures/DMChannel.js
index 570eb1d..8c18285 100644
--- a/src/structures/DMChannel.js
+++ b/src/structures/DMChannel.js
@@ -110,7 +110,6 @@ class DMChannel extends Channel {
       this.client.api
         .channels(this.id)
         .call.ring.post({
-          usingApplicationJson: true,
           data: {
             recipients: null,
           },
diff --git a/src/structures/Message.js b/src/structures/Message.js
index 520ec4a..8175c79 100644
--- a/src/structures/Message.js
+++ b/src/structures/Message.js
@@ -999,8 +999,7 @@ class Message extends Base {
    * @returns {boolean}
    */
   async markUnread() {
-    await this.client.api.channels[this.channelId].messages[this.id].ack({
-      usingApplicationJson: true,
+    await this.client.api.channels[this.channelId].messages[this.id].ack.post({
       data: {
         manual: true,
         mention_count:
diff --git a/src/structures/PartialGroupDMChannel.js b/src/structures/PartialGroupDMChannel.js
index 84e28da..92ca002 100644
--- a/src/structures/PartialGroupDMChannel.js
+++ b/src/structures/PartialGroupDMChannel.js
@@ -215,8 +215,7 @@ class PartialGroupDMChannel extends Channel {
       this.client.api
         .channels(this.id)
         .call.ring.post({
-          usingApplicationJson: true,
-          data: {
+          body: {
             recipients: null,
           },
         })