I fly all the time in class C and D airspace. I am doing a job in the morning here in Indianapolis class C zero airspace. I have a waiver and clearance from the tower, for tomorrow. (4 hours).
this area space you are showing a class C. F.Y.I. as long as you stay under 400 ft
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and you do an dji unlock you should be ok, and without a waiver. now that being said, make sure that are not any other local laws, like here in Indiana, the airport authority, like for UAS pilots to fill out an form on their online server, letting them know that you are flying by one of their airports here in Indiana.
now with all that being said...I believe that if you did everything that you said that you did, it might your drone updating the software unlock within itself, meaning the unlock from DJI. My drone, sometimes, especially in-between batteries swaps do not recognize the previous, unlock, meaning I have to go back into the settings and do the unlock again, just for the same unlock. The unlock request from DJI is still there, I just have to re-imported it into the drone again. If I know that I am going to be flying the next day in a controlled airspace, I do the unlock the night before, from the web site, and imported it in into my drone. at least if I am out at the site, and if I have to keep re-importing the unlock, then it is already loaded into my controller. I think it is one of the features from DJI that's needs to be fixed. Especially when I am using Pix4dcapture or just even the DJI app. sometimes, in-between the battery swaps I do not have to re-import, and something I do have to, before the drone motors turn on, and allow me to take off.
also looking at where you are flying, you will get some type of warning from the app, even with the un-locked, just letting you know are flying next to a controlled airspace, and I cannot remember the message right off hand, but some type of warning, like you are flying next to a controlled airspace, and I am pretty sure, it does display a red message, if I remember correctly. this is normal. I have seem this message, several times in the past.
I hope this makes sense. I do not think you did anything wrong.
I am flying Here:
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