model number? and have you updated the firmware yet? Did you try to reset and repair them? As my knowlege, reset plays an important role to solve many issues. I reset our router and got it working...

Any specific network request? Like how many ports do you need? Any advanced features? More details will be better.

Weird, all devices work properly except the macbook. While it is worth doing some troubleshooting on the current issue, cause only the mac failed. Any specific symptom that shows macbook does not...

per user manual, flashing red means that The powerline extender is experiencing poor signal strength, which is affected by the powerline environment; While it is invisible, it is hard to see any...

Tried to hard reset it yet? If not, refer to the user manual to reset it first. Still the same, show a video of its weird light status.

Follow https://www.tp-link.com/en/faq-2231.html to do some troubleshooting and narrow down the issue; with more details, it will be easier to fix it.