Urine Culture positive after antibiotics

I had a positive urine culture and was prescribed Amoxicillin 500mg, 3 times a day for 20 tablets (approximately 6–7 days). After completing the full course, I repeated the urine culture, and it still showed positive for the same bacteria. My doctor confirmed that the bacteria is sensitive to amoxicillin, so they prescribed the same antibiotic again — another 20 tablets, to be taken 3 times a day. However, this time, I have no symptoms at all (no burning, pain, frequency, etc.). I felt symptoms during the first infection but not now. I’m seeking a second opinion to understand: Is it necessary to treat again even though I have no symptoms? Could this be a case of asymptomatic bacteriuria that doesn’t require treatment? Should I consider other tests (e.g. ultrasound, kidney function, or further urine testing) if the culture stays positive? Are there any risks in taking another course of antibiotics when I'm not symptomatic?