Block Explorer Zksync http://www.stes.tyc.edu.tw/xoops/modules/profile/userinfo.php?uid=3670142 So, if there is a large number of transactions during the mempool therefore you paid out a comparatively low transaction cost, your transaction can continue to be unconfirmed for an extended period of time considering the fact that miners/validators will find transactions with better costs ... https://hedgedoc.k8s.eonerc.rwth-aachen.de/yOgaY6dNQA-nyetpp3bGPw/