diff --git a/src/EPPlus/Data/PowerQuery/ExcelPowerQueryMetaDataEntry.cs b/src/EPPlus/Data/PowerQuery/ExcelPowerQueryMetaDataEntry.cs
index c0872575c..1ebf15ee7 100644
--- a/src/EPPlus/Data/PowerQuery/ExcelPowerQueryMetaDataEntry.cs
+++ b/src/EPPlus/Data/PowerQuery/ExcelPowerQueryMetaDataEntry.cs
@@ -153,11 +153,11 @@ public string GetValueAsText(CultureInfo culture)
             }
             if (Value is int i)
             {
-                return "l" + i.ToString();
+                return "l" + i.ToString(CultureInfo.InvariantCulture);
             }
             if (Value is DateTime dt)
             {
-                return "d" + dt.ToString("yyyy-MM-ddTHH:mm:ss.fffffffZ");
+                return "d" + dt.ToString("yyyy-MM-ddTHH:mm:ss.fffffffZ", CultureInfo.InvariantCulture);
             }
             if (Value is bool b)
             {
@@ -165,11 +165,11 @@ public string GetValueAsText(CultureInfo culture)
             }
             if (Value is double d)
             {
-                return "f" + d.ToString();
+                return "f" + d.ToString(CultureInfo.InvariantCulture);
             }
             else
             {
-                return "s" + Value.ToString(); //You shoul never end up here.
+                return "s" + Value.ToString(); //You should never end up here.
             }
         }
         /// <summary>
diff --git a/src/EPPlusTest/Data/ConnectionTests.cs b/src/EPPlusTest/Data/ConnectionTests.cs
index 6fc695598..12499eddb 100644
--- a/src/EPPlusTest/Data/ConnectionTests.cs
+++ b/src/EPPlusTest/Data/ConnectionTests.cs
@@ -3,7 +3,9 @@
 using OfficeOpenXml.Data.Connection;
 using System;
 using System.Data.Common;
+using System.Globalization;
 using System.Text;
+using System.Threading;
 using System.Xml;
 
 namespace EPPlusTest.Data
@@ -193,10 +195,26 @@ public void ReadEPPWebPowerQuery()
                 SaveAndCleanup(p);
             }
         }
+        
         [TestMethod]
-        public void AddPivotTableWithConnection()
+        public void GetValueAsText_DateTime_ShouldUseInvariantCulture()
         {
+            var cc = Thread.CurrentThread.CurrentCulture;
+            try
+            {
+                Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo("fi-FI");
+                var entry = new ExcelPowerQueryMetaDataEntry("FillLastUpdated",
+                    new DateTime(2026, 2, 19, 8, 15, 36, DateTimeKind.Utc));
+                var result = entry.GetValueAsText(CultureInfo.GetCultureInfo("fi-FI"));
+                Assert.IsTrue(result.Contains(":"),
+                    $"Expected colon as time separator but got: {result}");
+            }
+            finally
+            {
+                Thread.CurrentThread.CurrentCulture = cc;
+            }
         }
+
         [ClassCleanup]
         public static void Cleanup()
         {
diff --git a/src/EPPlusTest/Issues/PackageIssues.cs b/src/EPPlusTest/Issues/PackageIssues.cs
index 4aa0d722d..92389dc46 100644
--- a/src/EPPlusTest/Issues/PackageIssues.cs
+++ b/src/EPPlusTest/Issues/PackageIssues.cs
@@ -1,6 +1,12 @@
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using OfficeOpenXml;
+using System;
+using System.ComponentModel;
 using System.Drawing;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Threading;
 
 namespace EPPlusTest.Issues
 {