Ask for leave with the leader, is it better to call or send a text message?

Ask for leave from the leader and call.

Think about the reasons for your leave, communicate with the leader by telephone in a consulting tone, and ask for the opinions of the leader. If the leader agrees, you have to fill out a leave of absence afterwards. If you don't agree, you have to wait for an opportunity to ask for leave. Short messages are not standardized, so try not to use them.