During each call to our API, your server makes a call to a DNS server, a kind of directory - to retrieve the location of the server mollie.com. This so-called DNS lookup usually takes less than a second, but from time to time it can take much longer because the nearest DNS server is too busy.
When this error message is a one-off event, there is really no reason to assume that there is something wrong with your server (or ours for that matter). However, when this error message starts making a regular appearance, you might consider taking a careful look at your DNS settings. In doing so, we would advise you to first check the cURL setting CURLOPT_CONNECTTIMEOUT. It allows you to set the waiting time for, among other things, the DNS lookup.
In PHP, you might consider making the following adjustment to increase the time-out to ten seconds:
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 10);