@harshakavuri 

Sadly, this is a known bug with the router that TPLink can't seem to fix. I came here with the same issue I think last year or the year before, which is a year after I purchased the router and pretty much the same answers were given. 

I haven't read all the replies here (I'm rushing atm) but I've had minor success with turning off auto channel switching. This is either going to work to your advantage or detriment, based on how crowded your area is with Wifi. If you leave it on one channel and 20 or 40 Mhz width, I almost guarantee it will work for longer. It still crashes for me but less so. It used to go down every 2 weeks to a month but now it's more like a month at a time. My Archer 5400 also has an issue where it won't automatically pick up the new IP when my carrier switches my IP address, but that's not so bad because they don't do it very often.

So, the recommendation is to try 20mhz channel width and set it to ONE channel and leave it there. If 20mhz is slow or devices can't connect, go to 40mhz. If you can get a free wifi analytics app on your phone, you can see what channels are crowded and stay off of those. Worst case scenario, grab a cheap router or access point and bridge the 2.4 GHz wifi and use that and use the 5ghz from the Archer. I myself bought a cheap mesh setup which ironically, never goes down. The only reason I don't switch over completely is that it's AC1200.

Anyway, good luck. I'm done with TP Link, there's no real support. The answers are canned and from a script or something and the people who answer on here don't seem to know anything about the product. TP Link routers also have a 1 year warranty and according to one of the folks (who work there), there are no FW updates guaranteed after that so this bug will likely never be fixed.

Time to try another brand. I'm going to just invest in another mesh setup, albeit with more 5ghz bands, etc.

@Bjaerven same here, no more 2.4 GHz Network. it was working previously, and a few months ago i update firmware, and i don't know if it is related.

Hi,

I wanted to add my voice to the chorus: I lose 2.4GHz frequently. It used to happen every few weeks, now it fails after 2 hours. Support is unwilling or unable to help. This is not acceptable, doubly so considering how expensive this router is! I've been a repeat customer but this will be my last TP-Link product. 

@formercustomer 

Just a heads up. The only way I've found around this while keeping the router useful is to add back in my old router and use it for 2.4 Ghz. I've turned off the 2.4Ghz radio on the C5400 and it's been smooth sailing since. I think this has to do with either a bad batch of chipset or perhaps heating/thermal issues. I don't know but so far I haven't had issues with the router. I would still like to move to using ONE router vs. three (lol) but at least now I can say that it's not been a complete waste of money. 

Good Luck!

Same thing here.

I just got off the chat with them today about this.  My 2.4 band continually drops out and I have rebooted, reset, change channels and width and it still drops out.  I told them about all the different models of TP-Link dropping the 2.4 band and all they said was it's out of warranty so they cannot help.  I know it's out of warranty but with all the same exact problems, they should know what's really going on and fix it.

Well, it's off to another brand, any ideas?  

I sent mine for repair. Here's what they found:

DAMAGED WI-FI SIGNAL INTERFACE

WI-FI SIGNAL CHIP SET CONTROLLER DAMAGED

SOLUTION: NO REPAIR

TP-Link never again!

@JoaoMachado 

This is why I didn't bother sending mine in. I got mine directly exchanged by Amazon after explaining the situation. However, sadly, Amazon replaced it with another C5400, which has the exact same issues. I honestly think there's a fatal flaw with these devices that cause the 2.4 Ghz chip to heat up and knock out. The longer you have it, the quicker it does it. The 5 Ghz chips don't seem to have this issue. I bet that TP Link knows about it, which is why they released a second C5400 (the C5400X) which is identical feature-wise. Nov 2018 to March 2019 was my initial go, and so March 2019 to Jan 2021 and it's finally off my network because of some more screwiness (won't surf to certain websites, even after turning off homecare). 

Anyway, good luck. 

My advice if you're going to ever buy TP Link - check the product forum like this one for issues before you buy. Do not trust the reviews, blogs, etc. Testing a device for 1 or 2 weeks isn't going to give you a true picture of how the device performs.

Add me to the list  of 2.4Ghz disappearing. I had my 5400 replaced with another 5400 and the problem is now worst. With the old unit, it happened maybe once in 7-10 days but with the new one, it happens every 3-4 days sometimes twice in 2 days. The router is fast when it's working.

What's everyone going with beside TP-Link?