Hello @Abdellah_Jbari_NUK The delivery throughput is shared with all channels and it is dependent on the active profile license you might have.
This is how Product documentation explains it:
The Peak Volume limits for emails and push notifications are a shared volume limit. For example, if Customer is licensing <2 million Active Profiles, the Peak Volume limit is 1.5 million, not 3 million and such 1.5 million limit is shared between the number of emails and push notifications sent by Customer.
My suggestion would be to check your allowed limit and throttle the sends.