Darkening around lips after using Retina-A-Micro.

Hi, I've been using Retina-A-Micro 0.08% for a couple of weeks and initially it was good but since four days the skin around my lips started turning darker and flakey and became even worse after been to an amusement park(I've been using sunblock and a hat the whole time). And I've been prescribed Solodyn 65mg and Spironolactone 25mg to take with food. Is this a permanent effect and how long does it take to fade. Do I need to do something to get rid of that.

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