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Use this: https://steemconnect.com/sign/delegateVestingShares?delegator=itstime&delegatee=centerlink&vesting_shares=40%20SP

Here are your errors:

  1. You need to enter the actual number and not AMOUNT
  2. You need a whitespace between 40 and SP. This is a little tricky and the solution is 40%20SP

%20 gets translated into whitespace by the browser.

Let me know if it worked!

Done !!

Thanks for the help.

@centerlink thanks for running the MSP project.

Glad to hear it :) Thank @aggroed & @ausbitbank, the founders of MSP :)

Thanks both of you

and thanks redacted from centerlink.