Errors

We seem to be getting intermittent erros which we can see on “Debug Events”

Event #10
Debug Event Details
Error
9th September 2021 at 2::07 pm
Mailer: Other SMTP SMTP Error: Could not authenticate.
WP Simple Paypal Shopping cart
/home/jnehegzp 'data1www/ebps.org.uk/wp· con1en1/plug1ns/wordpress-s1mple-paypal0shopp1ng-
cart/paypal.php (line:289)

This is the code from paypal.php

287: if ( ! empty( $notify_email ) ) {
288: 	    if ( get_option( 'wpspc_send_seller_email' ) ) {
289:		wp_mail( $notify_email, $seller_email_subject, $seller_email_body, $headers );
290:		$this->debug_log( 'Notify Email successfully sent to ' . $notify_email, true );
	    }

We have 12 “Events” logged, all with the same error text
We also have successfully received many emails so this problem is “intermittent”
The errors seem to start on 12 August 2021 and run through to 10th September 2021
This is page 2

Event #12
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	Wordfence Security	10th September 2021 at 5:34 pm
Event #11
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	Wordfence Security	9th September 2021 at 5:15 pm
Event #10
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	WP Simple Paypal Shopping cart	9th September 2021 at 2:07 pm
Event #9
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	WP Simple Paypal Shopping cart	9th September 2021 at 2:07 pm
Event #8
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	Wordfence Security	1st September 2021 at 9:40 am
Event #7
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	WP Simple Paypal Shopping cart	30th August 2021 at 8:19 pm
Event #6
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	WP Simple Paypal Shopping cart	30th August 2021 at 8:19 pm
Event #5
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	WP Simple Paypal Shopping cart	22nd August 2021 at 8:24 pm
Event #4
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	WP Simple Paypal Shopping cart	22nd August 2021 at 8:24 pm
Event #3
Error	Mailer: Other SMTP SMTP Error: Could not authenticate.	Wordfence Security	19th August 2021 at 4:06 pm