diff --git a/lib/utils/action-utils.js b/lib/utils/action-utils.js
--- a/lib/utils/action-utils.js
+++ b/lib/utils/action-utils.js
@@ -361,13 +361,13 @@
 
 export type ActionFunc<F> = (callServerEndpoint: CallServerEndpoint) => F;
 export type BindServerCall = <F>(serverCall: ActionFunc<F>) => F;
-type BindServerCallsParams = {
-  dispatch: Dispatch,
-  cookie: ?string,
-  urlPrefix: string,
-  sessionID: ?string,
-  currentUserInfo: ?CurrentUserInfo,
-  connectionStatus: ConnectionStatus,
+export type BindServerCallsParams = {
+  +dispatch: Dispatch,
+  +cookie: ?string,
+  +urlPrefix: string,
+  +sessionID: ?string,
+  +currentUserInfo: ?CurrentUserInfo,
+  +connectionStatus: ConnectionStatus,
 };
 
 // All server calls needs to include some information from the Redux state
diff --git a/native/account/registration/connect-ethereum.react.js b/native/account/registration/connect-ethereum.react.js
--- a/native/account/registration/connect-ethereum.react.js
+++ b/native/account/registration/connect-ethereum.react.js
@@ -135,7 +135,18 @@
     });
   }, [navigate, params]);
 
-  const exactSearchUserCall = useServerCall(exactSearchUser);
+  const { keyserverURL } = userSelections;
+  const serverCallParamOverride = React.useMemo(
+    () => ({
+      urlPrefix: keyserverURL,
+    }),
+    [keyserverURL],
+  );
+
+  const exactSearchUserCall = useServerCall(
+    exactSearchUser,
+    serverCallParamOverride,
+  );
   const dispatchActionPromise = useDispatchActionPromise();
 
   const cacheContext = React.useContext(ENSCacheContext);
@@ -215,6 +226,7 @@
         closing={panelState === 'closing'}
         onSuccessfulWalletSignature={onSuccessfulWalletSignature}
         setLoading={siwePanelSetLoading}
+        keyserverCallParamOverride={serverCallParamOverride}
       />
     );
   }
diff --git a/native/account/registration/username-selection.react.js b/native/account/registration/username-selection.react.js
--- a/native/account/registration/username-selection.react.js
+++ b/native/account/registration/username-selection.react.js
@@ -67,10 +67,21 @@
     return true;
   }, [validUsername]);
 
-  const exactSearchUserCall = useServerCall(exactSearchUser);
+  const { userSelections } = props.route.params;
+  const { keyserverURL } = userSelections;
+  const serverCallParamOverride = React.useMemo(
+    () => ({
+      urlPrefix: keyserverURL,
+    }),
+    [keyserverURL],
+  );
+
+  const exactSearchUserCall = useServerCall(
+    exactSearchUser,
+    serverCallParamOverride,
+  );
   const dispatchActionPromise = useDispatchActionPromise();
   const { navigate } = props.navigation;
-  const { userSelections } = props.route.params;
   const onProceed = React.useCallback(async () => {
     if (!checkUsernameValidity()) {
       return;
diff --git a/native/account/siwe-panel.react.js b/native/account/siwe-panel.react.js
--- a/native/account/siwe-panel.react.js
+++ b/native/account/siwe-panel.react.js
@@ -16,6 +16,7 @@
 import {
   useServerCall,
   useDispatchActionPromise,
+  type BindServerCallsParams,
 } from 'lib/utils/action-utils.js';
 
 import { commCoreModule } from '../native-modules.js';
@@ -36,10 +37,14 @@
   +onSuccessfulWalletSignature: SIWEResult => mixed,
   +closing: boolean,
   +setLoading: boolean => mixed,
+  +keyserverCallParamOverride?: $Shape<BindServerCallsParams>,
 };
 function SIWEPanel(props: Props): React.Node {
   const dispatchActionPromise = useDispatchActionPromise();
-  const getSIWENonceCall = useServerCall(getSIWENonce);
+  const getSIWENonceCall = useServerCall(
+    getSIWENonce,
+    props.keyserverCallParamOverride,
+  );
 
   const getSIWENonceCallFailed = useSelector(
     state => getSIWENonceLoadingStatusSelector(state) === 'error',