Letrozole 5mg vs 7.5mg...HELP!

So I’m on my 5th round of Letrozole. First 3 rounds were 2.5. They didn’t work. Then on to 5mg with a trigger shot and I got pregnant. But miscarried at 5-6 weeks... would you do another round of 5mg or ask your doctor to bump it up to 7.5? Even though I got pregnant on 5mg I wonder if I would have a better chance at a successful pregnancy with 7.5? Has anyone got pregnant on 5mg a second time with a trigger? Would love some insight on what worked!