[Issues getting "logged out of SL" as I am teleporting.]

I wasn't having many problems before when I teleported to a different area but now it seems like every other time I get "logged out of SL", how do I fix it? Plus, I get logged out when I am just standing and talking to others. 

I've tried to research the issue, but I just got lost with all the other information. 

It's been really frustrating. 

How can I fix it? 

TIA

[I bought some items recently and haven't received them. what should I do?]

I just bought some items on marketplace and haven't received them. What should I do?