LH test question

I’ve been taking LH tests morning and night for the past 3-4 days now because I’m supposed to ovulate soon. Well, they were getting slowly darker but never hit a surge. Yesterday they started getting lighter! I don’t know what this means. I haven’t changed when I’ve tested and I’ve made sure to have a concentrated urine every evening. Anyone know what this means? The bottom one was the darkest it got, then after that they got lighter so I stopped taking pictures