@Noah94
Hi, for your issue, we would like to do some troubleshooting to identify the issue first.
Please refer to this FAQ to troubleshoot at first: https://www.tp-link.com/support/faq/2233/
If still the same issue, can you help us confirm some information:
1. Please let us know the troubleshooting steps you have tried in detail, thank you!
2. What about the LED Status on RE when this issue happens?
3. May I know the problem occurs on 2.4G or 5G Wi-Fi? How long do you have this RE and when did the issue start?
4. The firmware and hardware version of RE: https://www.tp-link.com/support/faq/315/
5. Did you put RE in very close to router (within)and check stability?
What is the model of the main router? Do you have a stable Wi-Fi connection from the main router?
6. If the RE Led is ON when the issue happens, please send us a photo of the IP address on computer: https://www.tp-link.com/support/faq/838/
Thank you for your precious time.
Have a nice day!