@Jazzy71 Have you checked this thread? https://community.tp-link.com/en/home/forum/topic/241534

@Krishankum59 Do you mean the SIM card cannot be detected? If that is the case, check this article: https://community.tp-link.com/en/home/forum/topic/261882

@cayc The engineer will help confirm if it can be downgraded.

@Internet-san Can we know the WAN connection type on the AX73? Have you observed this when you first install the router, or this happens recently?

@cayc Sorry to know the firmware update caused issues to the connection. We would like to escalate the case to the support engineers, they will help analyze the issue and fix it.

@Viraj_s What is the device that connecting to the 2.4G network, what's the brand and model of the wireless adapter if it is a computer? Check the link speed when it is connected to the 2.4G network...