I have working code containing at the top:

using namespace Microsoft.Azure.Commands.ResourceManager.Cmdlets.SdkModels
using namespace Microsoft.Azure.Commands.Common.Authentication.Abstractions

Import-Module "AzureRm"

In the middle of my code I define variables of type [IStorageContext] and [PSResourceGroupDeployment]. When the script opens in VS Code, these types are flagged as not found by PSScriptAnalyzer, but found after changes. Similarly, this same code is being flagged by PSScriptAnalyzer in PowerShell Gallery.