I am having humidity issues in my house, humidity levels are not going down below 68% which is very high and due to which we are having mold issues.
Mine is a 4yr old home, 2 storied, energy efficient home, and 5500 heated SQFT. An AC technican was at my place to check the issue and he said my HVAC unit is small for my home.
I have two units one for each story and they are carrier indoor unit model FB4CNP042 and outdoor unit model CH14NB042 and when the technician mentioned that these are small for my home and potentially not holding up the humidity levels I checked with my neighbors (at least 9 exact same model homes) and and they have carrier Indoor unit model FB4CNP048 and Outdoor unit model CH14NB042-A. So we figured my indoor unit if different and small low performance from rest of all the houses in my community. When we reached out the company who installed these units in our home, they said they probably installed this indoor unit for us due to a back order issue and they said it should not make any difference in the performance anyway. However, we believe there is a reason why they installed that combination of indoor and outdoor units in all other houses for better performance and they messed up mine and hence its not maintaining cooling and humidity levels. Could someone please advise if this combination of Indoor and outdoor units I have is not enough for my home and hence humidity issues?

My Indoor Unit is 3.5 Ton. My outdoor Unit is 3.5 Ton
My Neighbors Indoor Unit is 4.0 Ton and their outdoor unit is 3.5 Ton

The AC company guy is saying Indoor unit capacity should match with outdoor unit or it can be higher. Others having a bigger indoor unit doesn't make any difference in this case?
Am not a technician, whatever the AC company guy saying is right?