First day ,after I buy it and download ,I am Android and my friend is IOS,we haven't buy any realm,we just invite and play,and the next day ,when she open,I join in her world like yesterday ,then always show me I cannot join the word!!!!

Until I open myself and I play myself like a silly in the big world ))after that,my friend try to join me as fast as she can ,but she can join me! My internet speed is better than her!!! Why I cannot join? Xbox also no problem ?Why???