Powershell connector - empty variables during updating

Hello folks!

During trying to update user object, for some reason OneIM seems is not passing parameters to the Powershell function. How it looks:

XML schema for user:

<ReadConfiguration>
				<ListingCommand Command="Get-UserList">
					<SetParameter Param="Address" Source="ConnectionParameter" Value="Address"/>
					<SetParameter Param="UsernameNPA" Source="ConnectionParameter" Value="UsernameNPA"/>
					<SetParameter Param="Password" Source="ConnectionParameter" Value="Password"/>
				</ListingCommand>
				<CommandSequence>
					<Item Command="Get-UserList" Order="1">
						<SetParameter Param="Address" Source="ConnectionParameter" Value="Address"/>
						<SetParameter Param="UsernameNPA" Source="ConnectionParameter" Value="UsernameNPA"/>
						<SetParameter Param="Password" Source="ConnectionParameter" Value="Password"/>
					</Item>
				</CommandSequence>
			</ReadConfiguration>
			<MethodConfiguration>
				<!--Define a method named "Insert"-->
				<Method Name="Insert">
					<!--An "Insert" consists of the following command calls-->
					<CommandSequence>
						<Item Command="Create-PAUser" Order="1">
							<SetParameter Param="Address" Source="ConnectionParameter" Value="Address"/>
							<SetParameter Param="UsernameNPA" Source="ConnectionParameter" Value="UsernameNPA"/>
							<SetParameter Param="Password" Source="ConnectionParameter" Value="Password"/>
						</Item>
					</CommandSequence>
				</Method>

				<Method Name="Update">
					<CommandSequence>
						<Item Order="1" Command="Update-PAUser" Condition="ModificationExists">
							<SetParameter Param="Address" Source="ConnectionParameter" Value="Address"/>
							<SetParameter Param="UsernameNPA" Source="ConnectionParameter" Value="UsernameNPA"/>
							<SetParameter Param="Password" Source="ConnectionParameter" Value="Password"/>
						</Item>
					</CommandSequence>
				</Method>

			</MethodConfiguration>

XML object properties:

				<Property Name="ID" IsMandatory="true" IsUniqueKey="true" DataType="String" IsDisplay="true" IsAutoFill="true">
					<CommandMappings>
						<Map Parameter="ID" ToCommand="Get-UserList"/>
						<Map Parameter="ID" ToCommand="Update-UserInfo"/>
					</CommandMappings>

					<ReturnBindings>
						<Bind Path="ID" CommandResultOf="Get-UserList"/>
						<Bind Path="ID" CommandResultOf="Update-UserInfo"/>
					</ReturnBindings>
				</Property>

	<Property Name="FirstName" IsMandatory="false" IsUniqueKey="false" DataType="String" IsDisplay="true">
					<CommandMappings>
						<Map Parameter="FirstName" ToCommand="Get-UserList"/>
						<Map Parameter="FirstName" ToCommand="Update-UserInfo"/>
					</CommandMappings>
					<ModifiedBy>
						<ModBy Command="Update-UserInfo"/>
					</ModifiedBy>
					<ReturnBindings>
						<Bind Path="FirstName" CommandResultOf="Get-UserList"/>
						<Bind Path="FirstName" CommandResultOf="Update-UserInfo"/>
					</ReturnBindings>
				</Property>



				<Property Name="LastName" IsMandatory="false" IsUniqueKey="false" DataType="String" IsDisplay="true">
					<CommandMappings>
						<Map Parameter="LastName" ToCommand="Get-UserList"/>
						<Map Parameter="LastName" ToCommand="Update-UserInfo"/>
					</CommandMappings>
					<ModifiedBy>
						<ModBy Command="Update-UserInfo"/>
					</ModifiedBy>
					<ReturnBindings>
						<Bind Path="LastName" CommandResultOf="Update-UserInfo"/>
						<Bind Path="LastName" CommandResultOf="Get-UserList"/>

					</ReturnBindings>
				</Property>

During browsing target system, object is returned correctly however try to modify object generates a call to function for UPDATE in powershell however when I tried to log passed parameters, the userName NPA, password are empty, null.

Error in short: "[1777007] Error committing 1 system objects. - Cannot bind argument to parameter 'username' because it is an empty string."

Version of One Identity - 8.2.1.

Variable set is filled, contain value.

Maybe any suggestions into what I can look?