Three months of UTI symptoms that keep flaring despite antibiotics usually means either the infection never fully cleared or a different bacteria is involved each time. Urispas only eases the burning and spasm, it doesn't treat the infection itself.
Next Steps
Please get a urine culture and sensitivity test done before starting any further antibiotic. This shows exactly which bacteria is present and which medicine will actually work, instead of trying another one blindly.
Health Tips
See a doctor urgently if you develop fever, pain in your back or sides, or blood in your urine, since that can mean the infection has reached your kidneys.