What can I do for telogen effluvium and now I have a receding hairline?

Telogen effluvium. Because telogen effluvium is a reactive process, which resolves spontaneously, treatment usually is limited to reassurance. Any reversible cause of hair shedding, such as poor diet, iron deficiency, hypothyroidism, or medication use, should be corrected. In our clinic we use B12 shots once a month which helps.
See a specialist. It is difficult to answer. You should see a hair loss specialist to determine the cause and appropriate treatment.

Related Questions

Does telogen effluvium and mild alopecia areata affect the hairline permanently?

Telogen effluvium. Because acute telogen effluvium is a reactive process, which resolves spontaneously, treatment usually is limited to reassurance. Any reversible cause of hair shedding, such as poor diet, iron deficiency, hypothyroidism, or medication use, should be corrected. Alopecia areata can be controlled with intralesional scalp cortisone injections. Your thyroid also needs to be checked.