What is the solution and what should I do when matters become easy at the outset but then become difficult upon their direct undertaking?

We do not know if the inability of the morsel to enter the mouth is a reality or an exaggeration of difficulties. If it is a reality, then it is unusual and could be due to the evil eye or sorcery. In this case, you should seek Ruqyah (definition) (Islamic exorcism) from righteous individuals, and beware of soothsayers. If what is meant is the difficulty of certain matters, then you must be patient and remember that everything is by Allah’s decree and destiny, and that Allah may know that goodness lies in depriving you of what you wish for. Increase your supplications, especially those for facilitating matters and overcoming difficulties.