Seeking advice on addressing the challenge of treating wastewater with high ammonia levels

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The COD of the influent water is around 8000, while the ammonia nitrogen level is between 170 and 200. After passing through the UASB, the COD drops to 1400, and the ammonia nitrogen level increases to 280. The flow rate of the influent water is 144 tons per day. UASB is followed by hydrolysis acidification + contact oxidation + facultative oxidation + activated sludge + flocculation sedimentation. Throughout this period, ammonia nitrogen levels remained constant. In the activated sludge stage, the ability to remove ammonia nitrogen was good for a while, and it was possible to reduce these levels to single digits; however, after about a month, ammonia nitrogen levels began to rise again, and now they have exceeded the allowable limit of 35. The moisture interface at the outlet of the activated sludge is clear, and the sludge settles relatively quickly – it takes about 5-10 minutes to settle. There are some issues with the flocs; they don’t resemble normal flocs. The supernatant is relatively turbid and yellowish; no obvious undissolved sludge can be seen, and a significant amount of sludge is generated after flocculation. (It is presumed that there is a large amount of fine sludge in the supernatant.) The company has two types of wastewater: one is high-concentration wastewater with an ammonia nitrogen level of around 400-500 ； The ammonia nitrogen concentration in low-concentration wastewater is around 1700–2500. Most of the components in the water quality are ammonia and ammonium ions ； There are also small amounts of organic nitrogen compounds such as acetonitrile, as well as hydrazine hydrate and others. Question: What is the acceptable ammonia nitrogen concentration for the above biochemical process? How can it be made compliant?