Getting "Authentication failed" error with code 105 when trying to access GetAccountsInfo API

Hello,

I'm trying to access GetAccountsInfo API and sending Request SOAP like in this doc:

https://video2.skills-academy.com/en-us/advertising/customer-management-service/getaccountsinfo?view=bingads-13#request-soap

This is the SOAP i'm sending:

<s:Envelope
	xmlns:i="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
	<s:Header
		xmlns="https://bingads.microsoft.com/Customer/v13">
		<Action mustUnderstand="1">GetAccountsInfo</Action>
		<AuthenticationToken i:nil="false">M.R3_BAY.****0</AuthenticationToken>
		<DeveloperToken i:nil="false">129****91</DeveloperToken>
	</s:Header>
	<s:Body>
		<GetAccountsInfoRequest
			xmlns="https://bingads.microsoft.com/Customer/v13">
			<CustomerId i:nil="false">f3****e</CustomerId>
		</GetAccountsInfoRequest>
	</s:Body>
</s:Envelope>

This is what I'm getting back:

<s:Envelope
	xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
	<s:Body>
		<s:Fault>
			<faultcode>s:Server</faultcode>
			<faultstring>Invalid client data. Check the SOAP fault details for more information. TrackingId: 375389be-2131-44aa-af39-eb9f6b07622b.</faultstring>
			<detail>
				<AdApiFaultDetail
					xmlns="https://adapi.microsoft.com"
					xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
					<TrackingId>375389be-2131-44aa-af39-eb9f6b07622b</TrackingId>
					<Errors>
						<AdApiError>
							<Code>105</Code>
							<Detail i:nil="true"/>
							<ErrorCode>InvalidCredentials</ErrorCode>
							<Message>Authentication failed. Either supplied credentials are invalid or the account is inactive</Message>
						</AdApiError>
					</Errors>
				</AdApiFaultDetail>
			</detail>
		</s:Fault>
	</s:Body>
</s:Envelope>

My account is active, I'm using production environment and my developer token is of "universal" type which should allow for multi-user / programmatic access.

Additionally I'm adding msads.manage in scope when requesting AuthenticationToken for above SOAP.

Could somebody please help me to understand why this is happening and how to address this?

Thanks,

Andrey