Hi Yoshinori,
I think it would be more natural to say:
I'm having a hard time learning English. Especially, my listening comprehension and speaking ability have not made much progress for a long time.
"Faced with difficulties" sounds like you are facing Objective 客観的 Difficulties (like perhaps a lack of money or of teachers, for example), which make it very difficult for you to progress. This may be true, i.e. you may actually lack the necessary time to study, and/or Japanese and English may objectively be very different, making English Objectively more difficult for you than Korean, for example. However, I think an English native speaker wouldn't use the phrase "faced with difficulties" and then immediately refer to your Abilities: they would instead tell the reader what those Objective Obstacles are (e.g. one of the above examples).
"I've been stuck in" implies that you have had to do something unpleasant for a long time, so "speaking skill and listening skill" is not something you are "stuck in." In this case you might say "my listening and speaking skills have been stuck at an intermediate level for ages," but to my ears it sounds strange to say "I've been stuck in" them.
By the way, you might be interested to know about a linguistics 言語学 term called "plateauing": it's as if you have been climbing a mountain and then you suddenly arrive at a plateau 高原 and so you stop going Upward, you just continue Forward without seeming to make Vertical Progress. So you could say "my listening comprehension and speaking skills plateaued プラトード a long time ago." But maybe normal native speakers might not use this expression very often... 🤓
Here are some ideas for you, in order to break out of your plateau:
- read interesting books in English (this was very important in helping me break out of my plateau in learning Japanese)
- listen to YouTube videos in English about topics that interest you (not language-learning videos, but videos made for English native speakers).