كتب : Hatem Maher
Fathi reportedly owes Hamid £71,000 dating back to his time at English second-division side Sheffield United.
The 25-year-old has been playing with Ahli since ending his brief English spell in 2007.
Renowned agent Nader Shawki, a close friend of Fathi, said the tough-tackling midfielder landed himself into trouble after making light of the issue.
"Fathi is in a difficult situation, he should pay Hamid's dues as soon as possible," Shawki, who is the agent of several prominent players including Sunderland's Ahmed Elmohamady, told FilGoal.com on Wednesday.
"FIFA's single judge ruled that Fathi should pay Hamid £71,000 long time ago but Fathi, unfortunately, did not care. That's why the matter is complicated now.
"Hamid should also receive 5% from that amount for every year as a penalty. That problem happened three years ago, so Fathi will probably have to pay Hamid more than £80,000.
"Fathi missed the deadline to lodge an appeal against the FIFA's decision so he doesn't have options. He could be eventually banned."
Ahli, already reeling following their African Champions League elimination at the hands of Tunisia's Esperance in the semi final, can ill afford to lose influential midfielder Fathi.
The former Ismaili man is an indispensable member of the Red Devils' squad, with his versatility giving coach Hossam Al-Badri plenty of options.
Fathi is a natural defensive midfielder but he also operates as right-back in Ahli's 4-4-2 formation.
Neither Ahli nor Fathi, whose contract runs out at the end of the season, commented on the issue.