Hi!  OMG I am like the most forgetful person ever!  Do you have that issue?
Sometimes my old memories are unable to be recalled from memory storage
That must be sad.  Especially if those are good memories... 
The amount of time the information is stored in the memory can be increased or decreased, it depends on the coding.
Coding of what?  The brain?  I am not sure how that works.  All I know is I put something down and I forget in like 4 mins!
Memory is a very complex mechanism of the brain.We still don/t know a lot about it.
True... You would think in 2018 we would have more answers.
Well, the  brain is the most complex organ we have.
Yes you said that. lol Well I just hope my memory gets better soon.
Memory retention improves with increased rehearsal.Try to do memory exercises and you will get better!