Language of all strings that has exactly 1 triple b I am new to automata and learning to make regular expression for languages. But I have been stuck on this one.

Suppose we have a language L, Language of all strings that has exactly 1 triple “b” defined over alphabet set Σ = {a, b}
Now after several tries, I came up with this
(a* (ab)* (ba)* )* bbb (a* (ab)* (ba)* )* but then I realize that this is wrong too because the string abbbabababb doesn't fit on this.

Kindly someone point out at my mistake or help me solve it as I have spent almost an hour on this.
It seems you are almost there.  You just need to care substrings with $abb$. One possible way is 
$R.E = (a^{*} (ba)^*(bba)^*)^*bbb(a^*(ab)^*(abb)^*)^*$

Note that I came upon this regular expression from the $FM$ of language you described. So, another way to find $R.E$ is from $FM$ directly.