diff --git a/.changes/refactor-problem.md b/.changes/refactor-problem.md
new file mode 100644
index 0000000..b6f6140
--- /dev/null
+++ b/.changes/refactor-problem.md
@@ -0,0 +1,5 @@
+---
+"algohub-server": patch:refactor
+---
+
+Allow get account by its surrealdb id (`Thing`).
diff --git a/Cargo.lock b/Cargo.lock
index d05f982..efbeaf8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -71,7 +71,7 @@ dependencies = [
 
 [[package]]
 name = "algohub-server"
-version = "0.1.3"
+version = "0.1.4"
 dependencies = [
  "anyhow",
  "chrono",
diff --git a/src/routes/account.rs b/src/routes/account.rs
index f39a5d9..240415b 100644
--- a/src/routes/account.rs
+++ b/src/routes/account.rs
@@ -106,7 +106,7 @@ pub async fn profile(db: &State<Surreal<Client>>, profile: Json<MergeProfile<'_>
 
 #[get("/profile/<id>")]
 pub async fn get_profile(db: &State<Surreal<Client>>, id: &str) -> Result<Profile> {
-    let profile = account::get_by_id::<Profile>(db, id)
+    let profile = account::get_by_identity::<Profile>(db, id)
         .await
         .map_err(|e| Error::ServerError(Json(e.to_string().into())))?
         .ok_or(Error::NotFound(Json("Account not found".into())))?;
diff --git a/src/routes/problem.rs b/src/routes/problem.rs
index d50497c..8653958 100644
--- a/src/routes/problem.rs
+++ b/src/routes/problem.rs
@@ -14,12 +14,13 @@ use surrealdb::{engine::remote::ws::Client, Surreal};
 
 use crate::{
     models::{
+        account::Account,
         error::Error,
         problem::{Mode, Problem, ProblemDetail, Sample},
         response::Response,
         OwnedCredentials,
     },
-    utils::{problem, session},
+    utils::{account, problem, session},
     Result,
 };
 
@@ -131,7 +132,7 @@ pub async fn get(
 #[derive(Serialize, Deserialize)]
 #[serde(crate = "rocket::serde")]
 pub struct ListProblem {
-    pub id: Option<String>,
+    pub identity: Option<String>,
     pub auth: Option<OwnedCredentials>,
     pub limit: Option<u32>,
 }
@@ -152,7 +153,22 @@ pub async fn list(
 
     let data = data.into_inner();
 
-    let problems = problem::list_for_account::<Problem>(db, data.id, authed_id, data.limit)
+    let account_id = if let Some(identity) = data.identity.clone() {
+        Some(
+            account::get_by_identity::<Account>(db, &identity)
+                .await
+                .map_err(|e| Error::ServerError(Json(e.to_string().into())))?
+                .ok_or(Error::Unauthorized(Json("Invalid identity".into())))?
+                .id
+                .unwrap()
+                .id
+                .to_string(),
+        )
+    } else {
+        None
+    };
+
+    let problems = problem::list_for_account::<Problem>(db, account_id, authed_id, data.limit)
         .await
         .map_err(|e| Error::ServerError(Json(e.to_string().into())))?;
 
diff --git a/src/utils/account.rs b/src/utils/account.rs
index 0316a66..9bf2f3f 100644
--- a/src/utils/account.rs
+++ b/src/utils/account.rs
@@ -59,9 +59,14 @@ pub async fn delete(db: &Surreal<Client>, id: &str) -> Result<()> {
     Ok(())
 }
 
-pub async fn get_by_identity(db: &Surreal<Client>, identity: &str) -> Result<Option<Account>> {
+pub async fn get_by_identity<M>(db: &Surreal<Client>, identity: &str) -> Result<Option<M>>
+where
+    for<'de> M: Deserialize<'de>,
+{
     Ok(db
-        .query("SELECT * FROM account WHERE username = $identity OR email = $identity")
+        .query(
+            "SELECT * FROM account WHERE username = $identity OR email = $identity OR record::id(id) = $identity"
+        )
         .bind(("identity", identity.to_string()))
         .await?
         .take(0)?)
diff --git a/src/utils/session.rs b/src/utils/session.rs
index 8930ba1..a20f351 100644
--- a/src/utils/session.rs
+++ b/src/utils/session.rs
@@ -1,7 +1,7 @@
 use anyhow::Result;
 use surrealdb::{engine::remote::ws::Client, sql::Thing, Surreal};
 
-use crate::models::account::Session;
+use crate::models::account::{Account, Session};
 
 use super::account;
 
@@ -41,7 +41,7 @@ pub async fn authenticate(
     identity: &str,
     password: &str,
 ) -> Result<Option<Session>> {
-    let account = account::get_by_identity(db, identity).await?;
+    let account = account::get_by_identity::<Account>(db, identity).await?;
     if account.is_none() {
         return Ok(None);
     };
diff --git a/tests/problem.rs b/tests/problem.rs
index b0319d2..b5b2eae 100644
--- a/tests/problem.rs
+++ b/tests/problem.rs
@@ -6,7 +6,7 @@ use algohub_server::{
     },
     routes::{
         account::{RegisterData, RegisterResponse},
-        problem::{ListProblem, CreateProblem, ProblemResponse},
+        problem::{CreateProblem, ListProblem, ProblemResponse},
     },
 };
 use anyhow::Result;
@@ -84,7 +84,7 @@ async fn test_problem() -> Result<()> {
     let response = client
         .post("/problem/list")
         .json(&ListProblem {
-            id: Some(id.clone()),
+            identity: Some(id.clone()),
             auth: Some(OwnedCredentials {
                 id: id.clone(),
                 token: token.clone(),
@@ -109,7 +109,7 @@ async fn test_problem() -> Result<()> {
     let response = client
         .post("/problem/list")
         .json(&ListProblem {
-            id: Some(id.clone()),
+            identity: Some(id.clone()),
             auth: Some(OwnedCredentials {
                 id: id.clone(),
                 token: token.clone(),