diff --git a/src/SIL.Machine.AspNetCore/Services/ClearMLAuthenticationService.cs b/src/SIL.Machine.AspNetCore/Services/ClearMLAuthenticationService.cs
index adbe3755b..9dba80f56 100644
--- a/src/SIL.Machine.AspNetCore/Services/ClearMLAuthenticationService.cs
+++ b/src/SIL.Machine.AspNetCore/Services/ClearMLAuthenticationService.cs
@@ -5,6 +5,7 @@ public class ClearMLAuthenticationService : BackgroundService, IClearMLAuthentic
     private readonly HttpClient _httpClient;
     private readonly IOptionsMonitor<ClearMLNmtEngineOptions> _options;
     private readonly ILogger<ClearMLAuthenticationService> _logger;
+    private readonly AsyncLock _lock = new();
 
     // technically, the token should be good for 30 days, but let's refresh each hour
     // to know well ahead of time if something is wrong.
@@ -25,11 +26,14 @@ ILogger<ClearMLAuthenticationService> logger
 
     public async Task<string> GetAuthToken(CancellationToken cancellationToken = default)
     {
-        if (_authToken is "")
+        using (await _lock.LockAsync())
         {
-            //Should only happen once, so no different in cost than previous solution
-            _logger.LogInformation("Token was empty; refreshing");
-            await AuthorizeAsync(cancellationToken);
+            if (_authToken is "")
+            {
+                //Should only happen once, so no different in cost than previous solution
+                _logger.LogInformation("Token was empty; refreshing");
+                await AuthorizeAsync(cancellationToken);
+            }
         }
         return _authToken;
     }
diff --git a/src/SIL.Machine.AspNetCore/Services/ClearMLHealthCheck.cs b/src/SIL.Machine.AspNetCore/Services/ClearMLHealthCheck.cs
index 55f9d6ff3..ced15ea5c 100644
--- a/src/SIL.Machine.AspNetCore/Services/ClearMLHealthCheck.cs
+++ b/src/SIL.Machine.AspNetCore/Services/ClearMLHealthCheck.cs
@@ -26,7 +26,7 @@ public async Task<HealthCheckResult> CheckHealthAsync(
         }
         catch (Exception e)
         {
-            _logger.LogError(0, exception: e, null);
+            _logger.LogError(e, null);
             return HealthCheckResult.Unhealthy(exception: e);
         }
     }