Something like this works just fine.

https://www.amazon.com/gp/product/B003V9TC10/

1. you lose air after unscrew it from the valve steam. https://www.amazon.com/Slime-2045-Metal-Valve-Extenders/dp/B003V9TC10/ref=sr_1_3?crid=6RXFDZLHD910&keywords=valve+stem+extender&qid=1662949347&sprefix=valve+stem+extende%2Caps%2C83&sr=8-3
2. use dish soap and water and spray around the tire surface to look for tiny bubble and around valve steam rubber.

if you have a leak on the tire surface, you can fix with tire plug https://www.amazon.com/HNDL-TIRE-PLUG-KIT-8PC/dp/B07NYL6BKZ/ref=sr_1_4?crid=2MEB4201QDNNW&keywords=tire+repair+kit+slime&qid=1662949479&sprefix=tire+repair+kit+silme%2Caps%2C68&sr=8-4

1. if you want to use sealant, this the the best one. it fixed my slow leak. I lost 20 psi in one night without riding.

https://armor-dilloz.com