Microsoft-Windows-Security-Auditing Eventcode: 4625 Unstoppable ex user log

An account failed to log on.
Subject: 
Security ID:    S-1-0-0 
Account Name:   - 
Account Domain: - 
Logon ID:   0x0
Logon Type: 3
Account For Which Logon Failed: 
Security ID:    S-1-0-0 
Account Name:   xyzuser 
Account Domain: srkt
Failure Information: 
Failure Reason: Unknown user name or bad password. 
Status: 0xc000006d 
Sub Status: 0xc0000064
Process Information: 
Caller Process ID:  0x0 
Caller Process Name:    -
Network Information: 
Workstation Name:   Compname 
Source Network Address: ipv4 
Source Port:    Randomhignumberport
Detailed Authentication Information: 
Logon Process:  NtLmSsp 
Authentication Package: NTLM 
Transited Services: - 
Package Name (NTLM only):   - 
Key Length: 0

This event is generated when a logon request fails. It is generated on the computer where access was attempted. The Subject fields indicate the account on the local system which requested the logon. This is most commonly a service such as the Server service, or a local process such as Winlogon.exe or Services.exe. The Logon Type field indicates the kind of logon that was requested. The most common types are 2 (interactive) and 3 (network). The Process Information fields indicate which account and process on the system requested the logon. The Network Information fields indicate where a remote logon request originated. Workstation name is not always available and may be left blank in some cases. The authentication information fields provide detailed information about this specific logon request.

• Transited services indicate which intermediate services have participated in this logon request.
• Package name indicates which sub-protocol was used among the NTLM protocols.
• Key length indicates the length of the generated session key. This will be 0 if no session key was requested.

A user name separated from our company and deleted from AD. He's trying to reach the File Server. It gets this error and it is trying again. There are more than 10000 logs in a weekly period. Every time it's tried from random ports.I found nothing for the solution on the internet.

How can i fix this?