If your new pen doesn't run out of water, you can try shaking it, which is also a common inspection method. Secondly, check whether the small straw in your pencil case tube has fallen off.
You can try scraping the fine seam on the nib with a blade. If you want to clean the nib thoroughly, you can gently pinch the nib with nail clippers and pull it out-note: not every nib can be pulled out like this, but most of them I have tried can.
Also, before using a new pen, remember to soak it in hot water, because most pen tips are protected by a layer of wax when they leave the factory. Remember to cover the pen cap after use, otherwise the ink will precipitate on the pen tip after volatilization.
Use blue or blue-black pen water first, and use black pen water first for newly bought pens, which will easily lead to no water, because the carbon in black carbon ink will be oxidized by air to form particles, so use blue or blue-black pen water for a period of time, let the new pen run in, and then use ink.