When your transaction is "pending," it means you wrote the letter, put a stamp on it, and dropped it in the mailbox. But the mailman hasn't picked it up yet, or he’s too busy with other letters.
Your wallet (MetaMask, Trust Wallet, etc.) communicates with the blockchain via an RPC (Remote Procedure Call) provider. Sometimes, your wallet loses sync with the blockchain. Your wallet says "Pending," but the blockchain has already dropped the transaction. uniswap transaction pending
How to do it (MetaMask):
When Uniswap asks you to confirm the gas fee, do not click "Low." When your transaction is "pending," it means you
Every wallet address has a counter called a "nonce." It starts at 0 and increases with every transaction you send (Nonce 1, Nonce 2, Nonce 3...). Validators process these in strict order. If you send Transaction #5 with a very low gas fee, Transaction #5 gets stuck. Consequently, Transaction #6, #7, and #8 cannot be processed until #5 clears. You have created a traffic jam in your own wallet. Sometimes, your wallet loses sync with the blockchain