My iPhone will only charge with a fast charger

As the title says, my iPhone 13 pro will only charge if I use a fast charger. It doesn’t charge with the regular square charging block that came in the box, and won’t work with any portable chargers, which is really annoying. I tried to get help at the Apple store but the employee who helped me had me buy another charging block and said all 13 pro models are like this. This was not true as my friends with newer models are able to charge their phones with a normal charging block. Is there any way I can troubleshoot this?