I wrote contract and deployed it on remix today but it takes over 5 min to confirm.And I tried to call function of deployed contract , but the transaction still takes several minutes and even I call transfer token from metamask, the transaction need unusual time to be confirmed.Anyone knows what happened?Is it a problem of Ethereum?Ropsten?or my walletaddress?(I've tried two but same problem happened)...
The network is very busy right now, resulting in higher gas prices. If you use a gas price that is too low, your transaction will take a lot longer to confirm. I recommend that you use ETH Gas Station to see what gas price you should use.
You can read more about gas in general here: https://support.mycrypto.com/general-knowledge/ethereum-blockchain/what-is-gas