having problem with error establishing a database connection

hello , i hope you are fine , i’m having this issue in my client website ,the site hosted on godaddy shared hosting , the site runes normally but sometimes when loading 2-3 pages or if the team working on site ( managing orders checking products ) the site just randomly shows error “establishing a database connection ” i contacted godaddy but their support is the worst ever , i’m sure its not from wp-config.php otherwise the site would not work at all , but the problem sometimes occur many times sometimes few times , please help me

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