Claim old Brave rewards

I have rewards that I have not been able to retrieve for some time. When I have my wallet verified with uphold then it shows the current balance of not much. When I de verify then the balance shows as much much more… which is what I had before I joined uphold. Also I have not had any pc brave ads for about 3 months now… mobile yes, pc no. If I clear all cookies will this zero my bat?