Blockchain Explorer Deutsch https://output.jsbin.com/nisuteliyi/ So, when there is a large number of transactions inside the mempool therefore you compensated a comparatively minimal transaction fee, your transaction can continue to be unconfirmed for an extended period of time since miners/validators will find transactions with increased charges to start with. The mempool https://wearethelist.com/story22251584/blockchain-explorer-analytics-and-web-services-a-simple-key-for-blockchain-explorer-btc-unveiled-https-cutt-ly-3rj9ygbc