Putrajaya does not use the STO system (only walk in is allowed), but from 1st November 2024 they say visitors should use the QMS app for getting a queue number. See:
https://www.imi.gov.my/index.php/pengumuman/qms-mobile-apps/
You can download the QMS app from Google Play or Apple Store.
Kuala Lumpur Immigration have announced they are going back to using the STO system.
So both Selangor and KL once again require applicants to make an STO appointment.
**UPDATE 10th June 2024**
Selangor Immigration have announced they are going back to using the STO system.
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It was announced on 31st May 2024 that the STO appointment system will no longer operate with effect from 1st June. Instead immigration will accept walk ins and there is a 'no wrong door policy'.
Renew your LTSVP online, but to collect the pass walk in rather than making an appointment.