Increase keyword ranking again. Help me go right

[thinkingforward]

Hi guys, I know there are too many questions like this, but if possible I still want to bother you for a few minutes to answer me and help me overcome this problem
My website (selling products) has existed for more than 1 year, and 6 months ago my site was in the 8th position of that keyword
I used to be like a robot when buying a lot of backlinks from BHW, Fiverr and Seoclerks (mostly blog comments, PBN, Web 2.0)
YES and now my site has dropped in rank
I just want to win 2-3 keywords in my product url (keyword volume is not high, this niche only about 4k-6k search per month)
I have looked at SEO packages on BHW but there are too many choices and prices along with the advertisements are too good so I am really confused and cannot give myself a right decision

My question is: Which method should I choose to increase the ranking of keywords that?

(My budget is around $500)
Thanks for visiting this post

 

[hideath]

So, you've basically bought some links that made you rank in the past, but not any longer,
And you want to buy more of these links that currently are not doing the work?
Do you see where's that going?

These links used to do the work, could do some work if well built nowadays,
But they're far from being as good or as worth as they used to,

Invest in some decent links if you want good long-lasting results,
Whenever they're guest posts from geniune websites, building/renting homepage pbns or any other type of links,

Your buget is tight for most niches, unless you're targetting super easy keywords,
Think about the ROI you'll be making, if you invest $10K and make $1K per month for 2 years, that's surely worth,

Lastly, make sure your current website is not actually penalized,
If it's the case, it would be a better choice to start with a new one instead

 

[thinkingforward]

So, you've basically bought some links that made you rank in the past, but not any longer,
And you want to buy more of these links that currently are not doing the work?
Do you see where's that going?

These links used to do the work, could do some work if well built nowadays,
But they're far from being as good or as worth as they used to,

Invest in some decent links if you want good long-lasting results,
Whenever they're guest posts from geniune websites, building/renting homepage pbns or any other type of links,

Your buget is tight for most niches, unless you're targetting super easy keywords,
Think about the ROI you'll be making, if you invest $10K and make $1K per month for 2 years, that's surely worth,

Lastly, make sure your current website is not actually penalized,
If it's the case, it would be a better choice to start with a new one instead

Yup, my website is working fine (definitely not penalized), only the keywords are dropping in rank from 8th to 60th :-(
I think maybe the backlinks I bought before were unstable and they were deleted, so this is the problem
So what packages should I buy now? Are PBNs or blog comments with high DA suitable?