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.
Brain
The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. The brain is located in the head, usually close to the sensory organs for senses such as vision. The brain is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons communicate with one
Forgetting
Forgetting or disremembering is the apparent loss or modification of information already encoded and stored in an individual's long-term memory. It is a spontaneous or gradual process in which old memories are unable to be recalled from memory storage. Forgetting also helps to reconcile the storage of new information with old knowledge. Problems with remembering, learning and retaining new information are a few of the most common complaints of older adults. Memory performance is usually related to the active functioning of three stages. These three stages are encoding,