Insomnia, not able to sleep without meds

Hi, I was diagnosed with hyperthyroidism(Graves Disease) in 2014-15, then was treated for a long 2 years for the same. I developed anxiety and severe insomnia that time. As per psychiatry consultation got treatment for the same with antidepressants (pexep-cr 12.5, mitraz, amital) and quitipine 25mg(sometimes 12.5mg). Psychiatric treatment was continued upto Nov+2018. Things improved over time. After that till now I was overall fine. But now again the sleep problem has started. I'm currently taking levothyroxine for my hypothyroid. Once graves disease was treated it was identified as hasimoto thyroditis with anti tpo of 870. Currently sleep problem constantly since 3 weeks. My thyroid TSH levels are now 2.85(thyronom dose is 62.5mcg), Ft4 is 1.67, ft3 is 2.64) but sleep is not coming on its own. I have consulted psychriatist and has been prescribed mirtaz 7.5 for 10 days and zolphidem 5mg. It's now 5th day but I can't still sleep with these medicines. What to do in this scenario?