Longman Dictionary of Contemporary English - 5th Edition (LDOCE5) cannot be found or downloaded onto my new phone

I purchased for LDOCE5 months ago.

Two days ago my iPhone6 just got shut off and the battery cannot be charged, so I now use my old iPhone5 instead (all information reset and use as a new phone).

I cannot download LCOCE5 as now newest version of Longman is 6th, though the 5th version in my iPad works just fine (I installed the app on both iPad and iPhone6 when I downloaded it).

In an app store it is like purchasing for another version is the only way I can use the dictionary.

When I went to Account > Purchased > Not in My Library (or All), LDOCE5 is nowhere to be found.

Is this normal to have to purchase a new version always?

Do I have to restore all of my iPhone6 data just to get the app?

If not, what do I do?