What's going on with my blue star fern?
Hey guys. This blue star fern has been with me for quite some time and grew on me. It seemed to be doing good recently. Multiple new sprouts and leaves. I cut it back a few weeks ago and wanted to repot it the upcoming week. However I saw this brown leaf today. My first guess was that it might got sunburned since it is outdoors on my balcony during summer (it gets ~14 h of light daily) but I always make sure, it's in the shade and the brown parts aren't dry or crispy.
Because of the warm weather I water twice a week with decalcified water and spray it in the morning and in the evening. I do believe it is potted in an orchid soil mix but I'm not 100% sure.
I want to give it the best life possible but I'm no expert with house plants. Google didn't really help with this. I appreciate any help. Thanks!