1st month off clomid but no ovulation.. why?

Jo

Ttc 4 years now. So I've been on clomid did 6 rounds. 4 successful ovulations 2 chemicals and 1 miscarriage.

Decided to take a break for a couple of months but still did opk's on the off chance. Normally ovulate cd 17 today is cd21 and still no ovulation

Has this happened to anyone else or anyone have any thoughts? Thanks