This question has been raised several times before. See here for an incomplete list of questions and answers:

https://www.researchgate.net/post/How_to_include_all_citations_on_RG_and_Google_scholar_citing_your_manuscript

https://www.researchgate.net/post/How_to_add_missing_citations_on_Google_scholar_Research_gate_and_Scopus

https://www.researchgate.net/post/Does_anybody_know_how_we_can_add_the_missing_citations_to_our_profile_in_Google_Scholar

https://www.researchgate.net/post/Does_anybody_know_how_we_can_add_the_missing_citations_in_Research_Gate_as_will_as_Google_Scholar_profile

https://www.researchgate.net/post/Does_any_know_how_can_I_add_missing_citations_to_google_scholar_and_resaerch_gate

https://www.researchgate.net/post/Is_there_any_to_add_the_missing_citations_in_Google_Scholar_Profile

https://www.researchgate.net/post/How_can_i_add_missing_citation_to_my_Google_Scholar_profile

https://www.researchgate.net/post/How_can_we_add_citations_in_google_scholar_and_Research_Gate_for_our_articles

https://www.researchgate.net/post/How_to_add_missing_citations_on_Google_Scholar

This question has been raised several times before. See here for an incomplete list of questions and answers:

https://www.researchgate.net/post/How_to_include_all_citations_on_RG_and_Google_scholar_citing_your_manuscript

https://www.researchgate.net/post/How_to_add_missing_citations_on_Google_scholar_Research_gate_and_Scopus

https://www.researchgate.net/post/Does_anybody_know_how_we_can_add_the_missing_citations_to_our_profile_in_Google_Scholar

https://www.researchgate.net/post/Does_anybody_know_how_we_can_add_the_missing_citations_in_Research_Gate_as_will_as_Google_Scholar_profile

https://www.researchgate.net/post/Does_any_know_how_can_I_add_missing_citations_to_google_scholar_and_resaerch_gate

https://www.researchgate.net/post/Is_there_any_to_add_the_missing_citations_in_Google_Scholar_Profile

https://www.researchgate.net/post/How_can_i_add_missing_citation_to_my_Google_Scholar_profile

https://www.researchgate.net/post/How_can_we_add_citations_in_google_scholar_and_Research_Gate_for_our_articles

https://www.researchgate.net/post/How_to_add_missing_citations_on_Google_Scholar

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