I bought a Wingsung 699 recently from AliExpress because I wanted to try out a vacuum filler. Ink leaks from around the nib whenever I cap it, leading to ink getting on the grip. When I write, blobs of ink sometimes burp out onto the page. Is this typical for this brand? I have another no name Wingsung (I think it’s actually a knockoff of the Hongdian dark forest) that has no issues.
On top of what others have said, it’s worth checking that the nib & feed are properly seated. I’ve had that happen with TWISBI’s before and that was the issue.