Fix errors in the code

I am looking for a programmer who has knowledge of hph js and laravell. Since I dont know exactly where the errors are. I say right away so that there are no questions. Site opencase (CSGO cases) Now to the task:
1) fix the error (after the upgrade mode, the item is not displayed in Steam)
2) correct the error (after the contract mode, the item is not displayed in Stim)
3) when canceling the sent item, the status on the site is not returned (if you send the item for purchase, the status is set. If you do not accept the trade exchange, the item does not return to the status available, but will remain in the status withdrawn)
4) when withdrawing some items, an error appears user not found or user not found1Prepared to pay an adequate price. According to the terms, it is desirable within a week