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Error Code 400520121 when booking a flight

cw9268949
Explorer C

After I click purchase, I keep getting this. IScreen Shot 2024-02-24 at 9.28.15 AM.png

 

I called the customer service and they basically said they weren't sure why I was getting this but they could book my flight for me.. but I've gotten this in the past and I don't want to call everytime to book a flight. Has anyone gotten this before and solved it?

2 REPLIES 2

Re: Error Code 400520121 when booking a flight

SoCalFlyer97
Frequent Flyer A

@cw9268949 wrote:

After I click purchase, I keep getting this. IScreen Shot 2024-02-24 at 9.28.15 AM.png

 

I called the customer service and they basically said they weren't sure why I was getting this but they could book my flight for me.. but I've gotten this in the past and I don't want to call everytime to book a flight. Has anyone gotten this before and solved it?


Hi! Other users have reported similar error codes when booking or checking in for their flights. This could occur if there's an IT-related network or device conflict. If you get a similar error when checking in or booking future flights, try these transactions through a different network connection (e.g.: different Wi-Fi network, cellular network, and not through a VPN). 

 

Note that sometimes, the error could also be related to the SW Rapid Rewards account or other technical problem; if that's the case and self-service transactions keep failing regardless of network connection type, I would certainly give SW an email so their IT staff can review this:

https://support.southwest.com/helpcenter/s/email-us

Click on "Comment/Question", "Southwest.com/SW App", "Functionality/Usability" and provide them with the error and incident codes.

 

However, you did the right thing by calling.

 

Hope this helps!

Re: Error Code 400520121 when booking a flight

cw9268949
Explorer C

Thank you for the response! I just e-mailed them.