Boards can be shared with either 'Read Only' access, or with 'Write Access'. Let's run through the process of ensuring your Board is shared with edit access.
To share your Board, in the menu bar you will see the option 'Share':
This will show two options, 'Share Boards' (sharing the Board as a 'Live' copy) and 'Send a Copy'.
If this option does not show in your menu bar, it might be that you have received the Board yourself as a copy with read only access. Our Support Team are always happy to help if you need this confirmed!
If sharing the Board as a 'Live' copy, you'll just need to add the recipient in question, ensure you have selected 'Write Access', then hit 'Give Permissions':
The process is similar for sharing a copy of the Board, you'll just need to ensure you have not selected the option 'Share as read only?':