I just figured out that the site sends me notices of women who are currently online in my mail box. I was interpreting those as notices of messages being sent to me from younger women and I was sending them messages confirming that I had received a message from them and asking them about themselves. One woman wrote back that I am her fathers age and was offended. The very wide age range on this dating site is confusing.

Don’t be embarrassed. You learned for next time. Welcome to Mingle.

I think that is a recent glitch that has been going on for a few months now. I figure I have a wide age range (29-59) but they still send me "matches" for 18 year olds. The only fix I have found is to go to the search section, put in their age and country, then click on the X so I do not see their profile again. Then don't forget to change the age and area of your search back to where you are looking when you are done...

It's not a glitch. Mingle admitted that they are trying to get different people to interact.

Many people for as many reasons chose only to date within a certain age group, others do not, providing of course both are free and able to marry. You are able to change the settings in your profile so only those within the age range you specify are able to contact you. Had the lady that was offended set her age range she would not have received your message, it is you that has been offended by her not doing so, through her own ignorance. (Go to settings and select Limit Who Can Send You Mail, if you wish to specify an age range).