Problems with WP all in one Import – utf-8 problem ?

Hello, i have some problem with my WP all in one import plugin (or wordpress itself i’m not sure).

Everything was working fine for long time, since few days my import file link is showing some encoded character in this link :

XML Link is valid, proofen and works fine (look at the end pl&currency=PLN)

https://api.ikonka.com.pl/api2/index.php/request/?format=xml&hash=a5894fd3a6175f38060436bb68e58f9c9a8229aa&variant=b&lang=pl&currency=PLN

Now my WP shows this link in wp all in one import : (pl¤cy=PLN)

https://api.ikonka.com.pl/api2/index.php/request/?format=xml&hash=a5894fd3a6175f38060436bb68e58f9c9a8229aa&variant=b&lang=pl¤cy=PLN

Is this UTF-8 encoding problem ? Wp ? Plugin ?

+ Nothing was changed, updated etc.

Screenshots:

https://freeimage.host/i/J0ITkEx
https://freeimage.host/i/J0ITeBj

I will be very thankful for your help guys

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