Bash file recode and 100% auto code maker and updater

I have a bash file that is linked to a [login to view URL] ( read by the amember membership site(google) and at present needs a revamp and fixed as two coders have let me down. Want i need: The script makes a code for a user and shows this on screen for the user to copy and paste. This is copied to a txt file that my other program reads, in the format it needs. Great and works ok for a year. But what it is not doing is the following: if a user makes a code after payment and comes back later to make a new one after payment, it does seem to be able to understand that there is 2 payments under that user (payment is put in a txt file for the code to check against) and this needs addressing as i have to then come on line to delete the old transaction for the user to be able to make their code. i would also like the code to auto update any dates in the text folder. 2 coders told me have coded in the [login to view URL] to do this and they havent. the code on server side is this F: J2k3RqFe8r V2tkhB2pr7 { enddate=2017-03-06 2300 } # User ID: 483, Name: first last # or MGUSER: srGdhtyj4n 77jgH23jxF { enddate=2017-12-15 1453 } # User ID: 169, Name: first last # or USER: srGdhtyj4n 77jgH23jxF { enddate=2017-12-15 1453 } # User ID: 169, Name: first last # the code makes a random user and password and then the enddate from the payment and then their user id on amember and then firstname lastname so i can easly see code. i need to be able to 100% auto update that endate, say a user buys a month line and next month pays, need the month to have +1 added, so 01 becomes 02 can chat more over it. Any auto spam bids from people not reading will be auto removed. Any silly bids will be removed, i already spent £200 on this and lost £200 from coders who didnt do the work. Beginning of any bid MUST have " fix and do 100% code "