This transaction requires a higher fee, or it will not be propagated to network.

[prashant.singh]

I am working on test network using electrum.

Sometimes when I try to send BTC to other addresses, with some value of amount I get hit by an error:
This transaction requires a higher fee, or it will not be propagated to the network.

while other values work well.

For eg,
When I try to send 1mBTC I get an error, when I send 10 mBTC everything is good.
When I send 600mBTC it's good, when I send 645mBTC I get the same error.

The fee slider is to max and I have selected dynamic fee. What can I do to send 1 or 645 or other values of amount

[kolloh]

I am working on test network using electrum.

Sometimes when I try to send BTC to other addresses, with some value of amount I get hit by an error:
This transaction requires a higher fee, or it will not be propagated to the network.

while other values work well.

For eg,
When I try to send 1mBTC I get an error, when I send 10 mBTC everything is good.
When I send 600mBTC it's good, when I send 645mBTC I get the same error.

The fee slider is to max and I have selected dynamic fee. What can I do to send 1 or 645 or other values of amount

What version of Electrum are you using? There was a bug in one of the older versions that caused the fees to not work correctly. Make sure you are running version 2.8.2 and see if that corrects the issue.