In WeTicket you can edit your capacity in two ways: total event capacity (maximum number of tickets available for the whole event) and a capacity per ticket type (maximum number of tickets available per ticket type).
Event capacity
Go to your event in WeTicket.
Navigate to the Calendar & Capacity section.
Adjust the Total Event Capacity to the desired number.
Click Save to apply the changes.
Capacity per ticket type
Go to 'Events and Stores'
Go to 'Settings'
And then to Tickets & Products
Find the ticket type you want to edit
Under the three dots click Edit and adjust the Available amount for that specific ticket.
Click Save to confirm the update.