Thanks all awsering me =) i'm using electrum, i used for a lot of months, with the lowest transaction, and never got this problem
As I wrote above, due to the increase of transactions, the fees have gone up significantly.
where is this child pays for parent"? i tried increase but still one satoshi per/b
Which version of Electrum do you have? The latest one should have Replace-By-Fee enabled by default. After clicking "Increase fee" you should see a slider which will allow you to set a higher transaction fee. There are currently 5 thousand unconfirmed transactions so it's slowly getting better. If it isn't urgent, wait a couple of hours and your transaction will be confirmed.