copyright Blockchain Explorer http://www.stes.tyc.edu.tw/xoops/modules/profile/userinfo.php?uid=3670142 So, when there is a lot of transactions while in the mempool and you also paid a comparatively very low transaction price, your transaction can continue to be unconfirmed for an extended timeframe due to the fact miners/validators will pick out transactions with better expenses 1st. https://listbell.com/story10073121/eth-blockchain-explorer-indicators-on-blockchain-explorer-meaning-you-should-know-https-cutt-ly-3rj9ygbc