diff --git a/pageserver/src/http/routes.rs b/pageserver/src/http/routes.rs
index 0dda6a29f964..b4220d160198 100644
--- a/pageserver/src/http/routes.rs
+++ b/pageserver/src/http/routes.rs
@@ -162,7 +162,6 @@ impl From<TenantSlotError> for ApiError {
                 ApiError::NotFound(anyhow::anyhow!("Tenant {tenant_id} not found").into())
             }
             e @ AlreadyExists(_, _) => ApiError::Conflict(format!("{e}")),
-            e @ Conflict(_) => ApiError::Conflict(format!("{e}")),
             InProgress => {
                 ApiError::ResourceUnavailable("Tenant is being modified concurrently".into())
             }
@@ -195,7 +194,6 @@ impl From<TenantMapError> for ApiError {
 impl From<TenantStateError> for ApiError {
     fn from(tse: TenantStateError) -> ApiError {
         match tse {
-            TenantStateError::NotFound(tid) => ApiError::NotFound(anyhow!("tenant {}", tid).into()),
             TenantStateError::NotActive(_) => {
                 ApiError::ResourceUnavailable("Tenant not yet active".into())
             }
diff --git a/pageserver/src/tenant/mgr.rs b/pageserver/src/tenant/mgr.rs
index ceadddeb7ebd..c46de7acb71d 100644
--- a/pageserver/src/tenant/mgr.rs
+++ b/pageserver/src/tenant/mgr.rs
@@ -860,8 +860,6 @@ pub(crate) async fn delete_timeline(
 
 #[derive(Debug, thiserror::Error)]
 pub(crate) enum TenantStateError {
-    #[error("Tenant {0} not found")]
-    NotFound(TenantId),
     #[error("Tenant {0} is stopping")]
     IsStopping(TenantId),
     #[error("Tenant {0} is not active")]
@@ -930,7 +928,12 @@ async fn detach_tenant0(
 
     // Ignored tenants are not present in memory and will bail the removal from memory operation.
     // Before returning the error, check for ignored tenant removal case — we only need to clean its local files then.
-    if detach_ignored && matches!(removal_result, Err(TenantStateError::NotFound(_))) {
+    if detach_ignored
+        && matches!(
+            removal_result,
+            Err(TenantStateError::SlotError(TenantSlotError::NotFound(_)))
+        )
+    {
         let tenant_ignore_mark = conf.tenant_ignore_mark_file_path(&tenant_id);
         if tenant_ignore_mark.exists() {
             info!("Detaching an ignored tenant");
@@ -1124,9 +1127,6 @@ pub(crate) enum TenantSlotError {
     #[error("tenant {0} already exists, state: {1:?}")]
     AlreadyExists(TenantId, TenantState),
 
-    #[error("tenant {0} already exists in but is not attached")]
-    Conflict(TenantId),
-
     // Tried to read a slot that is currently being mutated by another administrative
     // operation.
     #[error("tenant has a state change in progress, try again later")]
@@ -1362,7 +1362,13 @@ where
     // The SlotGuard allows us to manipulate the Tenant object without fear of some
     // concurrent API request doing something else for the same tenant ID.
     let attached_tenant = match tenant_slot {
-        Some(TenantSlot::Attached(t)) => Some(t),
+        Some(TenantSlot::Attached(t)) => {
+            if t.current_state() != TenantState::Active {
+                tenant_guard.upsert(TenantSlot::Attached(t))?;
+                return Err(TenantStateError::NotActive(tenant_id));
+            }
+            Some(t)
+        }
         _ => None,
     };