How to treat instances of PhoneNumberUtil class from C# port of Java library (libphonenumber-csharp)?

Question

I'm using a C# port (libphonenumber-csharp) of what is originally a Java library to parse phonenumbers into the correct format. However, I'm a bit confused as to how I should approach the "instance" of the PhoneNumberUtil class. The following snippet (from the source code, shortened to only include relevant parts) shows how you are supposed to get an instance:

public class PhoneNumberUtil
{
    // Summary:
    //     Gets a PhoneNumbers.PhoneNumberUtil instance to carry out international phone
    //     number formatting, parsing, or validation. The instance is loaded with phone
    //     number metadata for a number of most commonly used regions.
    //     The PhoneNumbers.PhoneNumberUtil is implemented as a singleton. Therefore, calling
    //     getInstance multiple times will only result in one instance being created.
    //
    // Returns:
    //     A PhoneNumbers.PhoneNumberUtil instance.
    public static PhoneNumberUtil GetInstance()
    {
        return instance ?? GetInstance("PhoneNumberMetaData.xml");
    }
    
    public static PhoneNumberUtil GetInstance(string baseFileLocation, Dictionary<int, List<string>> countryCallingCodeToRegionCodeMap = null)
    {
        lock (ThisLock)
        {
            return instance ?? (instance = new PhoneNumberUtil(baseFileLocation, null, countryCallingCodeToRegionCodeMap));
        }
    }
}

Maybe I'm just getting confused by the "Instance"-terminology but I struggle in understanding how I should instantiate this in my code. From what I'm used to see I would expect a Util class to be static and then I would not need care about instantiating but rather just call methods like PhoneNumberUtil.Parse(args...) or similar. Would it make sense to save the intance in private static field as such:

using PhoneNumbers;

internal static class PhoneNumberHelper
{
    private readonly static PhoneNumberUtil _phoneNumberUtil = PhoneNumberUtil.GetInstance();
    private const string SwedishCountryCode = "SE";

    public static bool TryParsePhoneNumber(string phonenumberToParse, out string result)
    {
        try
        {
            var phoneNumber = _phoneNumberUtil.Parse(phonenumberToParse, SwedishCountryCode);
            result = phoneNumber.CountryCode.ToString() + phoneNumber.NationalNumber;
            return true;
        }
        catch (Exception ex)
        {
            result = string.Empty;
            return false;
        }
    }
}

Or should I rather just always call the GetInstance() method like this:

using PhoneNumbers;

internal static class PhoneNumberHelper
{
    private const string SwedishCountryCode = "SE";

    public static bool TryParsePhoneNumber(string phonenumberToParse, out string result)
    {
        try
        {
            var phoneNumber = PhoneNumberUtil.GetInstance().Parse(phonenumberToParse, SwedishCountryCode);
            result = phoneNumber.CountryCode.ToString() + phoneNumber.NationalNumber;
            return true;
        }
        catch (Exception ex)
        {
            result = string.Empty;
            return false;
        }
    }
}

Does any of this even matter? Maybe I mix up static and singleton a bit?