Erro ao remover com hibernate

package entity;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;


@Entity
@Table(name = "cheque")
public class Cheque implements java.io.Serializable{
	
	private int ID;
	private String banco;
	private String conta;
	private String n;
	private String data;
	private float valor;	
	private Servicos servico;
	
	public Cheque() {
		
	}
	
	@Id
	@GeneratedValue
	@Column(name = "codigo")
	public int getID() {
		return this.ID;
	}
	
	public void setID(int ID) {
		this.ID = ID;
	}
	
	@Column(name = "banco")
	public String getBanco() {
		return this.banco;
	}
	
	public void setBanco(String banco) {
		this.banco = banco;
	} 
	
	@Column(name = "conta")
	public String getConta() {
		return this.conta;
	}
	
	public void setConta(String conta) {
		this.conta = conta;
	}
	
	@Column(name = "n")
	public String getN() {
		return this.n;
	}
	
	public void setN(String n) {
		this.n = n;
	}
	
	@Column(name = "dataa")
	public String getData() {
		return this.data;
	}
	
	public void setData(String data) {
		this.data = data;
	}
	
	@Column(name = "valor")
	public float getValor() {
		return this.valor;
	}
	
	public void setValor(float valor) {
		this.valor = valor;
	}
	
	@ManyToOne(cascade = CascadeType.ALL)
	@JoinColumn(name = "servicos_codigo")
	public Servicos getServico() {
		return this.servico;
	}
	
	public void setServico(Servicos servico) {
		this.servico = servico;
	}
}

package entity;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.OneToOne;
import javax.persistence.Table;
import entity.Carros;
import entity.Cheque;

@Entity
@Table(name = "servicos")
public class Servicos implements java.io.Serializable {
	
	private int ID;
	private float preco;
	private String data2;
	private String obs;
	private String restricao;
	private String financeira;
	private String dataRecibo;
	private float taxas;
	private float desconto;
	private Carros carro;
	private Cliente cliente;
	private Lojas loja;
	private float avista;
	private float acheque;
	private float cartao;
	private float promissoria;
	
	public Servicos() {
		
	}
	
	@Id
	@GeneratedValue
	@Column(name = "codigo")
	public int getID() {
		return this.ID;
	}
	
	public void setID(int ID) {
		this.ID = ID;
	}
	
	@Column(name = "preco")
	public float getPreco() {
		return this.preco;
	}
	
	public void setPreco(float preco) {
		this.preco = preco;
	}
	
	@Column(name = "data_2")
	public String getData2() {
		return this.data2;
	}
	
	public void setData2(String data2) {
		this.data2 = data2;
	}
	
	@Column(name = "obs")
	public String getObs() {
		return this.obs;
	}
	
	public void setObs(String obs) {
		this.obs = obs;
	}
	
	@Column(name = "restricao")
	public String getRestricao() {
		return this.restricao;
	}
	
	public void setRestricao(String restricao) {
		this.restricao = restricao;
	}
	
	@Column(name = "financeira")
	public String getFinanceira() {
		return this.financeira;
	}
	
	public void setFinanceira(String financeira) {
		this.financeira = financeira;
	}
	
	@Column(name = "dataRecibo")
	public String getDataRecibo() {
		return this.dataRecibo;
	}
	
	public void setDataRecibo(String dataRecibo) {
		this.dataRecibo = dataRecibo;
	}	
	
	@Column(name = "taxas")
	public float getTaxas() {
		return this.taxas;
	}
	
	public void setTaxas(float taxas) {
		this.taxas = taxas;
	}
	
	@Column(name = "desconto")
	public float getDesconto() {
		return this.desconto;
	}
	
	public void setDesconto(float desconto) {
		this.desconto = desconto;
	}
	
	@ManyToOne(cascade = CascadeType.ALL)
	@JoinColumn(name = "carros_codigo")
	public Carros getCarro() {
		return this.carro;
	}
	
	public void setCarro(Carros carro) {
		this.carro = carro;
	}
	
	@Column(name = "dinheiro")
	public float getAvista() {
		return this.avista;
	}
	
	public void setAvista(float avista) {
		this.avista = avista;
	}
	
	@Column(name = "cheque")
	public float getAcheque() {
		return this.acheque;
	}
	
	public void setAcheque(float acheque) {
		this.acheque = acheque;
	}
	
	@Column(name = "cartao")
	public float getCartao() {
		return this.cartao;
	}
	
	public void setCartao(float cartao) {
		this.cartao = cartao;
	}
	
	@Column(name = "promissoria")
	public float getPromissoria() {
		return this.promissoria;
	}
	
	public void setPromissoria(float promissoria) {
		this.promissoria = promissoria;
	}
	
	@ManyToOne(cascade = CascadeType.ALL)
	@JoinColumn(name = "cliente_codigo")
	public Cliente getCliente() {
		return this.cliente;
	}
	
	public void setCliente(Cliente cliente) {
		this.cliente = cliente;
	}
	
	@ManyToOne(cascade = CascadeType.ALL)
	@JoinColumn(name = "lojas_codigo")
	public Lojas getLoja() {
		return this.loja;
	}
	
	public void setLoja(Lojas loja) {
		this.loja = loja;
	}
}