What is the ruling on the prayers of those who pray on a prayer rug that has been contaminated with urine, while fearing it has not been properly cleaned, and do I need to repent?

If the carpet being stained with urine is merely a doubt, then do not pay attention to it. However, if you are certain of its impurity, then it is obligatory to wash it by pouring water on the defiled spot until it becomes pure; wiping it with water is not sufficient. You must repent and seek forgiveness. If the situation reoccurs, do not be ashamed of anyone, for Allah is more deserving of your shame. The prayer of whoever prayed on this carpet is valid, even with the presence of impurity, because they prayed without knowing about it.