Based on Names we need to get id

I have a form named as " contact" i have field " client name"

if i gave client names as "Ashok Kumar" then client id must be as " AK-1",

2) Arjun Kumar - AK-2

if the first letters are same the number should be increased like ws-1,ws-2,ws-3 if not it should be in the format XX-1

Below I have attached a screenshot of contact report i need an output in this format SS-1,SS-2,KJ-1 , but i got the output as SS-1,SS-2,KJ-3

Here is the code which i have tried, but i am not getting the expected output.

firstVal = input.Lead_Name.getprefix(" ").subtext(0,1);

lastVal = input.Lead_Name.getsuffix(" ").subtext(0,1);

stringval = (firstVal + lastVal).toUppercase();

contactObj = Contact_Form[ID != null];

checkPreffix = Contact_Form[Client_id == stringval];

//collection

if(contactObj.count() == 0 && checkPreffix == checkPreffix)

{

idVal = stringval + "-" + 1;

//info idVal;

}

else if(contactObj.count()>=1)

{

contactsObj = Contact_Form[ID != null].Client_id sort by Added_Time desc;

val = contactsObj.getsuffix("-");

temp = val.toLong();

temp = temp + 1;

idVal = stringval + "-" + temp;

info idVal;

}