Bellingham has denied the claims, after he was shown a red card in the first-half of Saturday's 1-1 draw.
Munuera Montero wrote in his referee's report: "In the 40th minute, Bellingham was sent off for the following reason: For addressing me, while I was just a few metres away, in the following terms: 'F*** you'."
If Munuera Montero's report stands, Bellingham faces a lengthy ban.
The rules state: "Insulting, offending or using insulting terms or attitudes towards the main referee, assistants, fourth referee, directors or sports authorities, unless it constitutes a more serious offence, will be punished with a suspension of four to twelve matches."