Opk cheap ones compared to digital opk

Hey guys so I need some help to see what you guys think and if you have went threw this. I started the digital clear blue advanced on cycle day 7 and got a low fertility same thing on cycle day 8. On cycle day 9 threw cycle day 18 I got high fertility on the clearblue advanced opk and a almost positive with the cheap amazon ones. On cycle day 19 I got a almost positive again with the cheap ones and a high fertility with the digital ones. Here I am on cycle day 20 and I got a for sure positive with the cheap ones but the digital still says high fertility. I’m not understanding why this is because ever the clearblue opk the lines when you take it out of the reader it looks positive. I’m gonna test one more time tomorrow with both because it said online and by my doctor you can ovulate from cycle day 11-21 when you have a 28-32 day cycle I had a 32 day cycle last month. Has anyone experienced this and if so what were the out comes. I’m still not giving up hope. I’ll post pictures!