After their breakup over Twitter, Chris Brown is allegedly trying his best to win back the heart of his former girlfriend Karrueche Tran, by any means necessary.

According to various sources, Brown has been calling Tran day in and day out, but looks like she is adamant about keeping away from him as she has, so far, refused to take his calls.

Tran announced that she is breaking up with Brown over Twitter, last week. The announcement came in right after news broke out that Brown is the father of a child named, Royalty. The mother of the child is his friend, Nia Amey.

Tran tweeted, saying, "Listen. One can only take so much. The best of luck to Chris and his family. No baby drama for me."

Brown, who has been dating Tran for almost six years now, reportedly had plans to have children with her but the model insisted on getting married first. Last year, in August he expressed his desire to have kids with Tran. He tweeted, saying, "@karrueche damn near 5 years and this woman still putting up with my s**t. Need to have this baby and stop playing!"

Reportedly, the couple had been having problems of another kind, even before the news of his kid broke out, according to E! News.

A source close to the couple, speaking to Hollywood Life, said, "Karrueche will never forget Chris Brown but"¦ she's so over this dude. "The relationship is over. She really can't do this with him anymore."

Nevertheless, Brown seems to be trying his best to win her back. A source close to Brown said, "Chris is still trying to get a hold of her and is calling and texting nonstop. She's not answering and doesn't have any plans to in the near future. She doesn't want any part of the drama," according to People Magazine.