I have a problem using lower_bound to find element in array by 2 parameters.

I have a

struct person{
    public:
    person(const std::string CITY, const std::string ADDRESS,
           const std::string REGION, const unsigned ID, std::string PARENT = "")
    : m_city(CITY), m_addr(ADDRESS), m_region(REGION), m_id(ID), m_parent(PARENT)
    {}

    std::string m_city;
    std::string m_addr;
    
    std::string m_region;
    unsigned m_id;
    
    std::string m_parent;
};

from this structs there is a std::vector

How can I find exact person using lower_bound in vector which is already sorted by Region?

My approach works the worst way. Most of the time it doesn't find anything.

auto iteratorRegion = findPerson(m_sortedByRegion, candidatePerson);

std::vector::iterator findPerson(std::vector& ARRAY,
                                         const person& candidatePerson) const {
    auto iterator = std::lower_bound(ARRAY.begin(), ARRAY.end(),
                                     candidatePerson, cityAdressComparator);
    if (iterator != ARRAY.end() && iterator->m_city == candidatePerson.m_city &&
        iterator->m_addr == candidatePerson.m_addr) {
        return iterator;
    }
    auto iterator2 = std::lower_bound(ARRAY.begin(), ARRAY.end(),
                                      candidatePerson, regionIDComparator);
    if (iterator2 != ARRAY.end() && iterator2->m_region == candidatePerson.m_region &&
        iterator2->m_id == candidatePerson.m_id) {
        return iterator2;
    }
    return ARRAY.end(); 
}

All comparators looks like this inside:

if (!(realEstateL.m_city == realEstateR.m_city))
{
    return realEstateL.m_city < realEstateR.m_city;
}
return realEstateL.m_addr < realEstateR.m_addr;