Are you sure you're not using some "safe internet" stuff e.g. Avast's one. --Vituzzu (talk) 09:01, 12 February 2020 (UTC)

@Vituzzu: Yes. I was editing a page then pressed the "Publish changes" button as usual & suddenly I saw the message that I'm not allowed to edit because of the IP block. Bi-on-ic (talk) 11:04, 12 February 2020 (UTC)
Basically you're connecting to Wikipedia through Digital Ocean, which is blocked. This can happen for a series of reasons, for example because you're using a VPN, some Avast/Avira/other antivirus vendors products, etc. Sometimes it can also happen in shared connections where you connection is filtered or you must login in order to use the Internet. Finally it can happen if there's some malware hijacking your connection,. --Vituzzu (talk) 14:23, 12 February 2020 (UTC)