NO Restore Purchase?

First I got Filterloop. I bought almost ALL the items.
Then I got the Pro Version (2nd) but even the « Restore pourchasse » option, it simply DOESN’T WORK. I tried to buy one filter to see. I saw. 0,99€ gone in 1 sec.
Funny that the Restore Purchase doesn’t « work » on THIS app… So difficult to make it work?? Why all others can?
Very very upset.

10dier about Filterloop Pro: Photo Editor, v3.1