In the two months that Ackquille Pollard, better known as the Brooklyn rapper Bobby Shmurda, has sat in jail on gang conspiracy and gun charges, his mother has visited twice a week. His hip-hop idols have offered words of support.

But Mr. Pollard says that he hasn’t heard what he wants from his label, Epic Records — namely a firm reassurance of its backing and help making his $2 million bail: “When I got locked up, I thought they were going to come for me,” he said in an interview from the Manhattan Detention Complex, “but they never came.”

Barely six months ago, Epic, a subsidiary of Sony, wooed Mr. Pollard, 20, with a seven-figure, multi-album deal, largely on the strength of one viral hit, known in its censored version as “Hot Boy.” With the label’s support, that song went on to reach No. 6 on the Billboard Hot 100.

But now, after Mr. Pollard’s electric performance on “The Tonight Show” and almost 1 million downloads sold — more than 800,000 for “Hot Boy” alone, according to Nielsen Music — Epic has distanced itself, declining, despite pleas from music industry figures like 50 Cent, to help the rapper get out.