It is common for throat pain to return if the underlying infection was not fully cleared, as a four-day course of amoxicillin-clavulanate is often shorter than the standard duration required for bacterial throat infections. It could also indicate a viral infection. Please do not restart any antibiotics, pantoprazole, or montelukast-levocetirizine without a doctor's guidance. I highly recommend consulting your healthcare provider for a throat examination to determine the exact cause and get the correct prescription. For temporary relief, you can gargle with warm salt water, drink warm fluids, and rest. This is a very common issue and easily manageable with the right evaluation.