R4i-SDHC (v1.4.1) WIFI broken on 1.4.5U DSi-XL

I have the R4i-SDHC WIFI 1.4.X.
I have an sdhc card which has only the firmware that they have from their site (v1.80b)When plugged into the DSi XL, it shows up (as Miami Knights) only if it is inserted when the DSi-XL is on. When I click on it, it says,
An error has occured. Press and hold the Power Button to turn the system off. Please see the Nintendo DSi Operations Manual for help troubleshooting.What do I do? I know my card works on 1.4.5, because there are many people that I have seen in videos on 1.4.5 and it works fine.My card is legit, I bought it from the official website (r4i-sdhc) and I did the truth inquiry thing and it says ok.Thanks,Oalecj

Just because some youtube video and it's website says it (the cart) supports DSi v.1.4.5, doesn't mean your cart can be upgraded to that kernel/firmware version on your already v.1.4.5 DSi console just like that. You will need to find an older NDS console to do the upgrading before you can use that cart on your DSi v.1.4.5. Your console running v.1.4.5 at this moment blocks any flash cartridges that hasn't been updated to support v.1.4.5.Just in case you're wondering;
1. No! You can't down-grade your DSi.
2. No! You can't update the cart using your already v.1.4.5 DSi.