Sorry to hear about it. I am assuming the 13th April is a typing error for 13th May.
So, you have been tested positive twice within a span of 3 weeks but the good news is that you have minimal to no symptoms. So, yes it can happen
Given that the infection or viral proteins takes time to clear up in some individuals. The evidence of the same lies with the Ct score which suggest that the infectivity is decreasing in your case.
Next Steps
Just follow 10 days of isolation, contact prevention and selff-hyegine so that you do not transmit it to anybody else. Apart from that you are good to go