diff --git a/Functions/Invoke-CoinbaseRequest.ps1 b/Functions/Invoke-CoinbaseRequest.ps1
index e28be87..8cebbf7 100644
--- a/Functions/Invoke-CoinbaseRequest.ps1
+++ b/Functions/Invoke-CoinbaseRequest.ps1
@@ -3,9 +3,7 @@ function Invoke-CoinbaseProRequest {
         [Parameter()] $Request    
     )
 
-    $EpochStart = Get-Date -Date "01/01/1970"
-    $Timestamp = (New-TimeSpan -Start $EpochStart -End (Get-Date).ToUniversalTime()).TotalSeconds
-    $Timestamp = ([math]::Round($Timestamp, 0)).ToString()
+    $Timestamp = Get-Date -UFormat %s
     $Prehash = $Timestamp + $request.method.ToUpper() + $request.url + $request.body
     $Signature_b64 = Get-HMAC -Message $prehash -Secret $request.secret
     $Header = @{
diff --git a/Functions/Private/New-CoinbaseProLimitOrder.ps1 b/Functions/Private/New-CoinbaseProLimitOrder.ps1
index c264dec..2097035 100644
--- a/Functions/Private/New-CoinbaseProLimitOrder.ps1
+++ b/Functions/Private/New-CoinbaseProLimitOrder.ps1
@@ -8,9 +8,9 @@ function New-CoinbaseProLimitOrder {
         [parameter(Mandatory=$true)]$Size,
         [parameter(Mandatory=$true)][ValidateScript({ Test-Product $_ })]$ProductID,
         [parameter()]$OrderID,
-        [parameter()][ValidateSet("dd","co","cn","cb")][string]$STP,
-        [parameter()][ValidateSet("GTC","GTT","IOC","FOK")][string]$TimeinForce,
-        [parameter()]$CancelAfter,
+        [parameter()][ValidateSet("dc","co","cn","cb")][string]$STP = "dc",
+        [parameter()][ValidateSet("GTC","GTT","IOC","FOK")][string]$TimeinForce = "GTT",
+        [parameter()][ValidateSet("min","hour","day")][string]$CancelAfter,    
         [parameter()][ValidateSet("true","false")]$PostOnly,
         [parameter()] [switch] $SandboxAPI
     )