Phone upgrade issues

I am trying to upgrade 3 of the phones on my account and am having major issues with my online account and app.  I am trying to take advantage of the sale that ends today, 12/1/19, and have been trying since Friday morning (now Sunday).  I went to the store Friday and the associate told me that I could purchase the phones online instead of waiting in line in store.  They told me that I just needed to make sure and checkout separately for each individual phone line.  I then made an attempt to do this Saturday morning.  I purchased the first phone with no issue, but then when trying to purchase the second phone the system tried to get me to add a line and would not let me purchase any more phones for the other lines.  I then contacted customer service and they said I had to add each phone individually to the cart and then check out.  They cancelled my original purchase so I could make the new one.  Once that was done, I opened my app and saw that I was logged out.  I then attempted to log in and it told me that I could not log in and that I would need to wait till the next day.  Called customer service again and they could not figure it out.  Went into the local store and same issue.  So I waited until today, was able to log in, and attempted the method that customer service told me to use.  Once again, unable to add more than 1 phone and when going back in the system was locked out and the system says I cannot log in until tomorrow when the sale is over.  Any help would be greatly appreciated.  I have 5 phone lines with Cricket and approximately 10 across multiple family members and would like to have a good experience with this purchase.