Google SERPs dropped then back in normal then drop again, Why?

We recently noticed most of our ranking pages used to ranked on 1st page at Google have gone nowhere now.

These problems happened and traffic dropped 50% on 16th of May. Then, we did some borken link fix on our site. Adjust the Googlebot crawl rate (we’re still not sure if these were the root cause).
On 20th-June, we see the traffic and ranking pages went back on track which is normal. But unfortunately, there is a drop again on 5th-August. It was 50% traffic dropped and most of our ranking pages not on first page now.

Does anyone here faced the same problem before? What could the casue SERPs drop > normal > drop again situation?

Please share your valuable inputs…

These troubles happened as well as their site traffic dropped at that month . They did some changes in their websites by Fix some broken links on the site and also Adjust the Googlebot crawl rate.

This topic has been covered in other threads.

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