Issues with animation spamming

Hello, I have a running animation imported and when I hold down A or D it works fine but I can just mash it and it looks janky. Please help

Code (CSharp):

1.  if (!m_Anim.GetCurrentAnimatorStateInfo(0).IsName("Slashing"))
2.           {
3.             if (Input.GetKey(KeyCode.Mouse0))
4.             {
5.                 if (Input.GetKey(KeyCode.D) && isGrounded)
6.                 {
7.                 Attack();
8.                 m_Anim.Play("Run Slashing");
9.                 }
10.                 else if (Input.GetKey(KeyCode.A) && isGrounded)
11.                 {
12.                 Attack();
13.                 m_Anim.Play("Run Slashing");
14.                 }
15.                 else
16.                 {
17.                 Attack();
18.                 m_Anim.Play("Slashing");
19.                 }
20.             }

 

In the animator click the transition and uncheck "Has exit time" for the run animation to the idle. This will remove the "jank"