Visitor Visa - B2

Hi Guys,

I'm a 25 year old female, married with 3 kids and have a good stable job. This forum has really been a great help with my preparation for my interview.

I went with my daughter for our interview on 16th July, however, we were not approved. See details below

Me: Goodmorning
VO: Goodmorning, may I have your passports please

VO: Is this your daughter?
Me: Yes

VO: Why do you want to go to the US?
Me: For vacation with my daughter

VO: What do you do for work?
Me: I'm an Operational Technician (supervisor) at the Bauxite Plant

VO: How long have you been working there?
Me: 7 years

VO: Are you legally married or in a common law relationship?
Me: Legally married

VO: How many children do you have?
Me: 3

VO: How old are the other two?
Me: 1 and 5

VO: Have you ever traveled outside of Guyana before?
Me: Yes

VO: Where?
Me: I was in the US twice when I was younger, Canada, Barbados, St. Vincent and Trinidad & Tobago

VO: What were the last two countries?
Me: Barbados in 2016 and St Vincent last year

VO: How long did you stay in Barbados?
Me: 4 days

VO: Did the kids go with you on these trips?
Me: They went with me to St Vincent but not in Barbados

VO: Why aren't they coming with you now?
Me: I don't think I would be able to manage all three of them on that long trip by myself

VO: What does your husband do for work?
Me: He's a contract driver for the hospital

VO: Why isn't he going with you
Me: He can't leave right now since he's on a contract

VO: Typing on computer

VO: Thank you for your time but according to the US Law I cannot give you a visa. *sips coffee and hands back passports*

Me: Thank you.

I was almost sure we would get it. I don't know what went wrong? Can you please let me know if it would be better to apply with my entire family next year? But I also saw in some cases they hardly give out visas to an entire family.

Please let me know what went wrong.