Copy SSRS Subscriptions from one SSRS server to another
you are using this PowerShell module from the gallery.
You need to use Copy-RsSubscription if the subscription on the destination does not already exist. Set-RsSubscription updates only already created subscriptions.
Get-RsSubscription -ReportServerUri 'http://sql2017/reportserver' -RsItem '/Cooperative Technologies/1035/1035YellowPages/Billing Reports/LookupActivityReport' | Export-RsSubscriptionXml &quot;c:\users\logsdone\desktop\SSRS Subscriptions\1.xml&quot;
Import-RsSubscriptionXml &quot;c:\users\logsdone\desktop\SSRS Subscriptions\1.xml&quot;  -ReportServerUri 'http://sql2017/reportserver'  | Copy-RsSubscription -ReportServerUri 'http://sql2017/reportserver' -RsItem '/Cooperative Technologies/1035/1035YellowPages/Billing Reports/LookupActivityReport'