Problem with Facebook Ads Leads

[ToniMontana]

Hi family,

I have a small offline telemarketing office and in the last few months
i started to advertise my business with facebook ads making lead ads
campaigns where people click on the image and give their contact number
so we can call them.
I am targeting people from my country and my native language and thats
about 2M overall and i was getting leads for like $2-$5 and having a great
ROI but recently after running this had for like 3 months now i am getting
leads for like $10 per lead even tough i didnt changed almost anything and
i only reach like 300-400k from my 2M audience overall.
Am i doing something wrong? do i need to make a new ad with different
image?
I really need some advice here since this is like my day job and %95 of
my offline income comes from those leads.
Thank you.

[ToniMontana]

Anyone here can give an advice?
Thank you!

[sewa]

I watched an offline fb ad course months ago and the author said that after 2+ months you need to change the ads cause people get tired of seeing same ads so you need to change your ads to increase roi again.

[ToniMontana]

I understand that but after running my ads for almost 3 months i can see that i only
covered 100k reach in total out of 2M audience, so i just cant understand the reason
why it jumped like 3 times more per lead then what it was till now if there is still more
reach to cover.