Can I get my 60-day stamp changed to a 90-day stamp for my Non-O visa after entering Thailand?

The original poster recently completed a 'visa run' to renew their multiple entry Non-O visa but was stamped in for only 60 days instead of the expected 90 days. They inquired if they could rectify this stamp error at a local immigration office in Nakhon Si Thammarat or Phuket. The community responded mainly pointing out that corrections for stamp errors made at land borders typically need to be fixed at the issuing border, and advised the poster to be more vigilant about checking stamps upon entry. It was also noted that Non-O visas usually grant a 90-day stay, and emphasized the importance of checking entry stamps meticulously.