Apex can not remove multiple spaces in String

Hello,

I am trying to remove all spaces from the following string:

howabountnow.com,,,itsme.com,,,name,,,hello.com,,,asdasdasdasd.asdasdasda,: :: :;;     ;;; ::   :: :; ; ;,, ,,, ,,, asdasd.asd,,, ,,,asdsadas,,,dilyan

and from the place where there are multiple spaces it is removed only one space and the result is:

DEBUG|domain1 howabountnow.com,,,itsme.com,,,name,,,hello.com,,,asdasdasdasd.asdasdasda,::::;;    ;;;::  :::;;;,,,,,,,,asdasd.asd,,,,,,asdsadas,,,dilyan

So far I've tried the following:

replaceAll('\s+', '');
replaceAll('[ ]+', '');
replace(' ', '');

and few more similar expressions.

At the moment I'm using the following source code:

String domain = accountObj.Domain__c;
    System.debug('domain ' + domain);
    integer spaceInd = domain.indexOf(' ');
    System.debug('spaceInd1: ' + spaceInd);
    while (spaceInd > -1) {
        domain = domain.replace(' ', '');
        spaceInd = domain.indexOf(' ');
        System.debug('spaceInd: ' + spaceInd);
    }
    System.debug('domain1 ' + domain);

When I start the code in debug log I get the following:

USER_DEBUG|[198]|DEBUG|domain howabountnow.com,,,itsme.com,,,name,,,hello.com,,,asdasdasdasd.asdasdasda,: :: :;;     ;;; ::   :: :; ; ;,, ,,, ,,, asdasd.asd,,, ,,,asdsadas,,,dilyan
USER_DEBUG|[203]|DEBUG|spaceInd1: 75
USER_DEBUG|[207]|DEBUG|spaceInd: -1
USER_DEBUG|[209]|DEBUG|domain1 howabountnow.com,,,itsme.com,,,name,,,hello.com,,,asdasdasdasd.asdasdasda,::::;;    ;;;::  :::;;;,,,,,,,,asdasd.asd,,,,,,asdsadas,,,dilyan

Could you please advise how to remove all spaces from the String or replace them with a single space in apex?

Regards,

Dilyan