Replacement 12V battery for CHR 2.0 hybrid 2020 model

I have had an issue with my 2020 CHR as it did not start after 7 days of no use. I measured the voltage on the Battery and it was around the 8V region.

I went with some of the recomandation from the forum and got a Yuasa YBX5012 Battery but when I try to fit it, all is well expect the breather pipe. The breather pipe connection does not match the breather hole in the Battery. I noticed that the original battery had an adaptor which I pulled out and tried to put in the new battery but it does not work. Did anyone find any adaptor or new breather connection for this type of battery or how did they manage to fit this battery?

Many thanks.

Normally there is a red plastic transport plug/bung in the hole on the Battery which you need pull out with pliers. Have you completely removed that? 

Yes, I have removed the plastic transport plug, its just that the hole in the new Battery is bigger than the connector. I noticed the original Battery had an adaptor, but this does not match the new Battery. 

To be honest, I could just add some tape to the breather connector and make it fit, but I was wondering if there is a more elegant way with buying some type of new adaptor, etc?

Might this work?