where is my recently deleted album

It depends on the system version on your iPhone, where the recently Deleted album is shown.

On the newer system versions it is shown under Albums > Utilities.

In Photos tap "Albums", then go directly down to the bottom of "Albums". You will see "Recently Deleted" all the way down under Utilities". Do not tap "See More" under "Albums" or you will see less. Stay in the "Albums" tab and do not switch to "My albums".

In older system versions the "Recently Deleted Album may not be shown at all, if it is empty.

Are you perhaps running out of storage in iCloud?

If you have used all cloud storage, the deleted photos will not be saved in Recently deleted, but will be deleted immediately permanently, until you have freed enough cloud storage.

Also, photos you delete from My Photo Stream or shared albums will not be saved in Recently Deleted.

You should be seeing Recently Deleted here: