Before you begin
Make sure that your iPhone or iPad is set to use the most compatible file formats. On your device, go to Most Compatible. Refer to Apple's support site if you need more information about High Efficiency Image File (HEIF) formats., and then tap
Tap your profile picture, tap Advanced, then select Compress Files Before Sending.
Select a compression setting:
Tap your profile picture, then tap Advanced and select Send Reduced File Size.