I have noticed when i bank money it disapeares so i have resorted to keepin my money on hand and it still glitches, for example i sold a good few lvl 700's pokemon and i should have gotten around 19,000,000,000 but when i clicked on a different page that disapeared too, in total i have lost over 200,000,000,000 down to it

The maximum capacity of Money able to be held in one place is $2,147,483,647.
You can have that much in your hand and in the bank.
If you exceed the limit, the money is lost.

Adding on to Icyslash, $2,147,483,647 is the maximum because it is the largest positive value of a number on any 32-bit operating system.

but why, their is pokemon on the market for say 2,000,000,000,000 why make that possible if we cant exceed the limit of 2B

Those can't be bought, meaning they rot in there until they just disappear when their time is up.

Wow that's sad to those Pokemon looks like around level 500 is the max amount you buy them at?

Will their be a time the site changes to a 64-bit so we can do these sort of things??

the amount of cash that u can keep is only $2.147bil..so once u sell ur poke it might seem that u have gotten so much cash..but it will dissappear once u reload or change the page