If you can log into one device, you should be able to log into all as it doesn't matter which device you use when accessing Collums. If you are having problems, please don't try another browser - Google Chrome is always the browser to use.
The most common reasons for this are:
incorrect url - your url is https://xxxxxx.auth.collums.co.uk/ where xxxxxx is your clinic name.
incorrect details entered. Please also try entering your details manually (rather than using a password manager) in case the wrong details have been saved.
Please check these 2 and let us know if you have further problems.