Schedule refresh greyed out - OneDrive refresh working

Hi, I am unsure whether this has been answered elsewhere, but couldn't find the relevant topic - apologies if duplicating.

I have a Report which pulls data from a series of files from Sharepoints within my Organisation. In addition to this there is one web link (a wiki page) which I use. 

I cannot set-up a schedule refresh and get the following message:
Error message for Schedule refresh (20 March)Onedrive refresh history (4 April)

Data sources

What is causing this to error like this? I can publish the report online fine from Power BI Desktop as demonstrated by the 'OneDrive' refresh success, however what prevents a Schedule refresh being set-up?

I have gone into the Data source settings to make sure that I am signed into each source correctly. They are as following:

Wiki page - Credential annonymous, privacy level public

Sharepoint site 1 - Credential organisation, privacy organisation (am signed into Microsoft account)

Sharepoint site 2- Credential organisation, privacy organisation (am signed into Microsoft account) 

Many thanks for any solutions.