diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index 90d4ab6..b190c0f 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -11,12 +11,12 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go: [ '1.18', '1.21' ]
+        go: [ '1.21' ]
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
     - name: Set up Go
-      uses: actions/setup-go@v3
+      uses: actions/setup-go@v5
       with:
         go-version: ${{ matrix.go }}
 
diff --git a/.github/workflows/golangci-lint.yml b/.github/workflows/golangci-lint.yml
index 1169dd4..4fdc07a 100644
--- a/.github/workflows/golangci-lint.yml
+++ b/.github/workflows/golangci-lint.yml
@@ -14,18 +14,18 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go: [ '1.18' ]
+        go: [ '1.21' ]
     steps:
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v5
         with:
           go-version: ${{ matrix.go }}
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v4
         with:
           # Optional: version of golangci-lint to use in form of v1.2 or v1.2.3 or `latest` to use the latest version
-          version: v1.45.2
+          version: v1.57.2
 
           # Optional: working directory, useful for monorepos
           # working-directory: somedir
diff --git a/go.mod b/go.mod
index a0f4358..4a9f699 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/free5gc/ngap
 
-go 1.17
+go 1.21
 
 require (
 	github.com/free5gc/aper v1.0.5
diff --git a/ngapConvert/TimeStamp.go b/ngapConvert/TimeStamp.go
index 6272dd8..5063c88 100644
--- a/ngapConvert/TimeStamp.go
+++ b/ngapConvert/TimeStamp.go
@@ -10,31 +10,30 @@ import (
 /*
 RFC 5905 Section 6 https://tools.ietf.org/html/rfc5905#section-6
 
-       0                   1                   2                   3
-       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-      |                            Seconds                            |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-      |                            Fraction                           |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
-                             NTP Timestamp Format
-
-   The 64-bit timestamp format is used in packet headers and other
-   places with limited word size.  It includes a 32-bit unsigned seconds
-   field spanning 136 years and a 32-bit fraction field resolving 232
-   picoseconds.  The 32-bit short format is used in delay and dispersion
-   header fields where the full resolution and range of the other
-   formats are not justified.  It includes a 16-bit unsigned seconds
-   field and a 16-bit fraction field.
-
-   In the date and timestamp formats, the prime epoch, or base date of
-   era 0, is 0 h 1 January 1900 UTC, when all bits are zero.  It should
-   be noted that strictly speaking, UTC did not exist prior to 1 January
-   1972, but it is convenient to assume it has existed for all eternity,
-   even if all knowledge of historic leap seconds has been lost.  Dates
-   are relative to the prime epoch; values greater than zero represent
-
+	    0                   1                   2                   3
+	    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |                            Seconds                            |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |                            Fraction                           |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+	                          NTP Timestamp Format
+
+	The 64-bit timestamp format is used in packet headers and other
+	places with limited word size.  It includes a 32-bit unsigned seconds
+	field spanning 136 years and a 32-bit fraction field resolving 232
+	picoseconds.  The 32-bit short format is used in delay and dispersion
+	header fields where the full resolution and range of the other
+	formats are not justified.  It includes a 16-bit unsigned seconds
+	field and a 16-bit fraction field.
+
+	In the date and timestamp formats, the prime epoch, or base date of
+	era 0, is 0 h 1 January 1900 UTC, when all bits are zero.  It should
+	be noted that strictly speaking, UTC did not exist prior to 1 January
+	1972, but it is convenient to assume it has existed for all eternity,
+	even if all knowledge of historic leap seconds has been lost.  Dates
+	are relative to the prime epoch; values greater than zero represent
 */
 func TimeStampToInt32(timeStampNgap aper.OctetString) (timeStamp int32) {
 	if len(timeStampNgap) != 4 {