Repeated Word Filling Context Window During Translation

API
1

Model: 4.1 nano : Prompt is simple and straightforward.

Input: English article with HTML tags and attributes ( ~5
Expected Output: Translated article in provided language parameter.

Issue:
When translating the English article to Georgian, the output starts fine but midway through the response, a single Georgian word is repeated continuously until the model hits the context limit (~32k tokens). The repeated word fills the rest of the output window unnecessarily, as shown in the screenshot.

Screenshot

The image shows a section of text that contains a mixture of code (likely HTML or similar markup) and non-Latin script content, with some lines repeating the same sentence multiple times. (Captioned by AI)
The image shows a section of text that contains a mixture of code (likely HTML or similar markup) and non-Latin script content, with some lines repeating the same sentence multiple times. (Captioned by AI)1258×196 16.9 KB

Is this a known issue with GPT-4.1-nano or a token overflow/looping bug? Any suggestions on how to handle or avoid this behavior during large translations?

2

We’ve been using gpt-4.1 nano for weeks with no such noticeable issue but today we have seen three instances of such token repetition. It feels like a regression occurred even if, AFAIK, there is only one checkpoint: 2025-04-14.

Examples:

[...] explicitly mentioning it in multiple sections (e.g., paras 4, 76, 86, 102, 106, 122, 132, 142, 182, 202, 217, 222, 227, 231, 237, 242, 247, 251, 256, 261, 266, 271, 276, 281, 286, 291, 296, 301, 306, 311, 316, 321, 326, 331, 336, 341, 346, 351, 356, 361, 366, 371, 376, 381, 386, 391, 396, 401, 406, 411, 416, 421, 426, 431, 436, 441, [and an and on]

[...] nor does it explicitly address constitutional issues related to racial profiling or systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic systemic  [and an and on]

[...] (see paragraphs <para>112, 113, 115, 120, 122, 129, 132, 139, 142, 145, 150, 154, 159, 170, 173, 176, 179, 182, 185, 188, 191, 194, 197, 200, 203, 210, 213, 217, 220, 223, 226, 229, 232, 235, 238, 241, 244, 247, 250, 253, 256, 259, 262, 265, 268, 271, 274, 277, 280, 283, 286, 289, 292, 295, 298, 301, 304, 307, 310, 313, 316, 319, 322, 325, 328, 331, 334, 337, 340, 343, 346, 349, 352, 355, 358, 361, 364, 367, 370, 373, 376, 379, 382, 385, 388, 391, 394,  [and an and on]