@MikeEarl 

Hi, for your issue, we would like to check the below information first.

May I know which line is connected to the VR400? It is telephone(DSL) line OR Ethernet cable?

When the issue happens, can you check if there is abnormal light on the router? Please tell me the lights' status on the router in detail for me.

May I know how many wireless clients are connected to the router? They all have the same issue?

Please try to restart the router to check if it works well again?

OR can the router recover the Wi-Fi connection automatically?

When the dropping issue happens, your wireless clients are still connected to the router's Wi-Fi, right? OR they are disconnected.

If the issue only happens on all the wireless clients, please check if both band 2.4GHz and 5GHz Wi-Fi have the same issue.

Please download Wi-Fi analyzer APP on your phone to test the empty channel for 2.4GHz and 5GHz Wi-Fi around.

Then follow the instruction to enter the management page of router, go to advanced-wireless-wireless settings to change the 2.4GHz and 5GHz channel to be empty one you have tested. https://www.tp-link.com/support/faq/1730/

Please also change the 2.4GHz channel width to be 20MHz, 5GHz channel width to be 20MHz and save.

Then reboot the router to check if the same issue happens again.

Note: To change the channel is to avoid much interface on both 2.4GHz and 5GHz band.

BTW, can you send us the white label of printed on the router for us to check the version?

If it still can't work well, please tell me the result of the above troubleshooting steps in detail.

Look forward to your reply.