diff --git a/packages/helpers/src/dkim/dns-archive.ts b/packages/helpers/src/dkim/dns-archive.ts
index 0eb84c60..964fd9b7 100644
--- a/packages/helpers/src/dkim/dns-archive.ts
+++ b/packages/helpers/src/dkim/dns-archive.ts
@@ -1,18 +1,18 @@
-import { CustomError } from "../lib/mailauth/tools";
+import { CustomError } from '../lib/mailauth/tools';
 
-const ZKEMAIL_DNS_ARCHIVER_API = "https://archive.prove.email/api/key";
+const ZKEMAIL_DNS_ARCHIVER_API = 'https://archive.prove.email/api/key';
 
 export async function resolveDNSFromZKEmailArchive(name: string, type: string) {
-  if (type !== "TXT") {
+  if (type !== 'TXT') {
     throw new Error(`ZK Email Archive only supports TXT records - got ${type}`);
   }
 
   // Get domain from full dns record name - $selector._domainkey.$domain.com
-  const domain = name.split(".").slice(-2).join(".");
-  const selector = name.split(".")[0];
+  const domain = name.split('.').slice(-2).join('.');
+  const selector = name.split('.')[0];
 
   const queryUrl = new URL(ZKEMAIL_DNS_ARCHIVER_API);
-  queryUrl.searchParams.set("domain", domain);
+  queryUrl.searchParams.set('domain', domain);
 
   const resp = await fetch(queryUrl);
   const data = await resp.json();
@@ -22,7 +22,7 @@ export async function resolveDNSFromZKEmailArchive(name: string, type: string) {
   if (!dkimRecord) {
     throw new CustomError(
       `DKIM record not found for domain ${domain} and selector ${selector} in ZK Email Archive.`,
-      "ENODATA"
+      'ENODATA',
     );
   }
 
diff --git a/packages/helpers/src/dkim/dns-over-http.ts b/packages/helpers/src/dkim/dns-over-http.ts
index ad09aa31..3481c1dd 100644
--- a/packages/helpers/src/dkim/dns-over-http.ts
+++ b/packages/helpers/src/dkim/dns-over-http.ts
@@ -1,11 +1,11 @@
-import { CustomError } from "../lib/mailauth/tools";
+import { CustomError } from '../lib/mailauth/tools';
 
 // DoH servers list
 export enum DoHServer {
   // Google Public DNS
-  Google = "https://dns.google/resolve",
+  Google = 'https://dns.google/resolve',
   // Cloudflare DNS
-  Cloudflare = "https://cloudflare-dns.com/dns-query",
+  Cloudflare = 'https://cloudflare-dns.com/dns-query',
 }
 
 /**
@@ -17,6 +17,7 @@ export enum DoHServer {
 export class DoH {
   // DNS response codes
   static DoHStatusNoError = 0;
+
   // DNS RR types
   static DoHTypeTXT = 16;
 
@@ -25,54 +26,53 @@ export class DoH {
    *
    * @static
    * @param {string} name DKIM record name (e.g. 20230601._domainkey.gmail.com)
-   * @param {string} DNSServer DNS over HTTPS API URL
+   * @param {string} dnsServerURL DNS over HTTPS API URL
    * @return {*}  {(Promise<string | null>)} DKIM public key or null if not found
    * @memberof DoH
    */
   public static async resolveDKIMPublicKey(
     name: string,
-    DNSServer: string
+    dnsServerURL: string
   ): Promise<string | null> {
-    if (!DNSServer.startsWith("https://")) {
-      DNSServer = "https://" + DNSServer;
+    let cleanURL = dnsServerURL;
+    if (!cleanURL.startsWith('https://')) {
+      cleanURL = `https://${cleanURL}`;
     }
-    if (DNSServer.endsWith("/")) {
-      DNSServer = DNSServer.slice(0, -1);
+    if (cleanURL.endsWith('/')) {
+      cleanURL = cleanURL.slice(0, -1);
     }
-    const resp = await fetch(
-      DNSServer +
-        "?" +
-        new URLSearchParams({
-          name: name,
-          // DKIM public key record type is TXT
-          type: DoH.DoHTypeTXT.toString(),
-        }),
-      {
+
+    const queryUrl = new URL(cleanURL);
+    queryUrl.searchParams.set('name', name);
+    queryUrl.searchParams.set('type', DoH.DoHTypeTXT.toString());
+
+    const resp = await fetch(queryUrl, {
         headers: {
-          accept: "application/dns-json",
+          accept: 'application/dns-json',
         },
       }
     );
+
     if (resp.status === 200) {
       const out = await resp.json();
       if (
-        typeof out === "object" &&
+        typeof out === 'object' &&
         out !== null &&
-        "Status" in out &&
-        "Answer" in out
+        'Status' in out &&
+        'Answer' in out
       ) {
-        const resp = out as DoHResponse;
-        if (resp.Status === DoH.DoHStatusNoError && resp.Answer.length > 0) {
-          for (const ans of resp.Answer) {
+        const result = out as DoHResponse;
+        if (result.Status === DoH.DoHStatusNoError && result.Answer.length > 0) {
+          for (const ans of result.Answer) {
             if (ans.type === DoH.DoHTypeTXT) {
               let DKIMRecord = ans.data;
               /*
-                                Remove all double quotes
-                                Some DNS providers wrap TXT records in double quotes, 
-                                and others like Cloudflare may include them. According to 
-                                TXT (potentially multi-line) and DKIM (Base64 data) standards,
-                                we can directly remove all double quotes from the DKIM public key.
-                            */
+                  Remove all double quotes
+                  Some DNS providers wrap TXT records in double quotes, 
+                  and others like Cloudflare may include them. According to 
+                  TXT (potentially multi-line) and DKIM (Base64 data) standards,
+                  we can directly remove all double quotes from the DKIM public key.
+              */
               DKIMRecord = DKIMRecord.replace(/"/g, "");
               return DKIMRecord;
             }
@@ -107,12 +107,12 @@ interface Answer {
 }
 
 export async function resolveDNSHTTP(name: string, type: string) {
-  if (type !== "TXT") {
+  if (type !== 'TXT') {
     throw new Error(`DNS over HTTP: Only type TXT is supported, got ${type}`);
   }
   const googleResult = await DoH.resolveDKIMPublicKey(name, DoHServer.Google);
   if (!googleResult) {
-    throw new CustomError("No DKIM record found in Google", "ENODATA");
+    throw new CustomError('No DKIM record found in Google', 'ENODATA');
   }
 
   const cloudflareResult = await DoH.resolveDKIMPublicKey(
@@ -123,7 +123,7 @@ export async function resolveDNSHTTP(name: string, type: string) {
   // Log an error if there is a mismatch in the result
   if (googleResult !== cloudflareResult) {
     console.error(
-      "DKIM record mismatch between Google and Cloudflare! Using Google result."
+      'DKIM record mismatch between Google and Cloudflare! Using Google result.'
     );
   }