The withdrawal function: where your contract records a right of withdrawal, the button Withdraw from contract here is in your HawkOpen settings, and the email confirming your purchase has a link that works without signing in. You confirm your decision for that contract, and HawkOpen sends you an email with the text of your statement and the date and time it was submitted. You can also send HawkOpen a clear statement in any other form.
HawkOpen gives the withdrawal function to every consumer contract, wherever you are billed; a purchase as a business (with a VAT ID entered at checkout) has none. The period is 14 days from the day the contract is concluded. If you start with the CRM trial, the trial and the paid continuation are one contract, so the 14 days count from the start of the trial. If the law that applies gives you a longer period or other rights, they apply.
Refund after a withdrawal: if you did not ask for the service to start during the withdrawal period, you get back everything you paid; if you expressly asked for an early start, you pay for the part of the service provided until you withdrew and get the rest back. HawkOpen refunds to the same payment method. Starting a subscription does not by itself take away a right of withdrawal you have.
Cancelling the renewal: in Settings you can cancel your plan at any time, and it then ends at the end of the paid period. That stops future payments; it is not a withdrawal and does not by itself refund the current period.