Spelling can be surprising! Analogous to "akklimatisere, "akkord", etc. I'd have expected "akceptere", but the dictionary agrees that "acceptere" is indeed spelled that way (only). Or is the "cc" not pronounced as "ks"?
"Accept" is a loanword from latin 'acceptum' and the spelling has not yet been 'danishized'. But for pronuonciation it is better to think of it as "aksept".