Discount Code not working

[MaeTimeless]

Discount codes cannot be applied although it has been set correctly. The same discount code applied for one user and was working fine. I sent the same code out as a marketing email could this be the case? Do users need to type it out? Please help because I have majority of people having the same issue on their end but what I don’t get is one person was able to use the code without problems.

[ColeensCloset]

I'm having the same problem - We want to go live with our website this evening but the discount code isn't working when im testing using my own mobile and viewing the site using the passcode- it says exactly the same - code isn't valid for the items in your cart.

I have set it for email subscribers - and i ticked this box when going through to checkout - any help would be much appreciated.

[ShampooSteve]

Anyone find a solution? 
I had a discount code that was working fine since November 2020.  This last week it stopped working.  Lots of customer complaints.

I deleted and recreated the discount code, no luck.

Could a Loyalty Program App somehow interfere with discount codes? That's the only thing that changed on the site.