can not connect to https website when use vpn

sorry English poor. hope you can understand me.

I have two device ,  A is xg85 , B is xg230

two device connect vpn

I have website for service in B company , use http and https in the same ip  192.168.1.15

http://192.168.1.15  ,https://192.168.1.15 are different website ,but use the same ip

in B site user connect both of these website very well .

in A site , when I connect http is very fast and ok . but when I connect https://192.168.1.15

then can not connect .... 

dns setting is all the same on A and B  , dns is setting 192.168.1.111 in B site

I test nslookup command to test from A and B, is all answer 192.168.1.15 .

before change  xg85 in A site ,I used juniper and xg 230 vpn to connect  https ,https all ok .

but when I change juniper to xg85 , then can not use https ... I don't change any dns setting

so I think is firewall issue .