Need helps about % Parts bonus in Exploration

hi, so far this is a great game! I have a few Survivors in my camp that I upgrade to 3-4 stars, mostly Rank C Survivors because it’s cheaper to get the bonus % to Weapon Parts found during Exploration. But I notice that the % percentage stopped going up at 1040% even though it supposed to be higher after I promoted my Survivors. Also I recently posted inquiries in the Help section but have not gotten replies, so I don’t know if I did it right or not, thank you for your help and keep up the great work!

Please update the app to fix any issues and get back to us in Support when you still have problems. Thanks.