Problems with Acrobat supplied with Dell machine

I purchased Acrobat and Microsoft Office as a bundle when purchasing a Dell Optiplex. The Acrobat was nominally a 3-year licence. It appeared to install OK when installing with the redemption code supplied by Dell. However, after 30 days it announced subscription has expired and inviting me to pay (as if it was just a free trial). I managed to get a new redemption code and it worked OK for 30 days and again quoted licence has expired. The installation has not been recorded on the records in my Adobe user. dell have offered no further help. How to get the Acrobat to run for the purchased term?