admin login error

When updating products, sometimes I get an error (posted on another thread) and when I reload page, this is what shows up

I took a screenshot - Success green bar does not belong there obviously

How many stores do you manage? Simultaneously?

I have found that OpenCart only knows how to keep track of one user-admin relationship at a time in a single browser. If you are trying to perform admin functions on two or more OpenCart stores at once, every time you make a submission on one store's tab you will invalidate the session tokens on all other stores' tabs you have going. The only way I have found to work around this is to open a different [brand of] browser for each additional store I need to manage simultaneously.

make sure the stores are on different domains or sub domains

I'm managing only one store
but I have OC set as multistore
I have multistore set up on subdomains

I'll try on a different browser and see if I get the same issues and I'll report back

FYI
Comp.... mac book pro
browser.... firefox 602