why do we get the error and unable to edit files

#devops

E325: ATTENTION
Found a swap file by the name ".tomcat-users.xml.swp"
owned by: root dated: Thu Feb 22 04:41:04 2024
file name: /opt/apache-tomcat-9.0.86/conf/tomcat-users.xml
modified: YES
user name: root host name: ip-172-31-17-216
process ID: 2503 (STILL RUNNING)
While opening file "tomcat-users.xml"
dated: Wed Feb 14 08:15:12 2024

(1) Another program may be editing the same file. If this is the case,
be careful not to end up with two different instances of the same
file when making changes. Quit, or continue with caution.
(2) An edit session for this file crashed.
If this is the case, use ":recover" or "vim -r tomcat-users.xml"
to recover the changes (see ":help recovery").
If you did this already, delete the swap file ".tomcat-users.xml.swp"
to avoid this message.

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