I Pad keeps failing to connect to web sites.

[HappydaysArehere]

This is doing this more and more frequently. Suddenly it asks me to check wi fi. My lap top is working perfectly. I then discovered if I turn the I Pad off completely it returns to normal when it comes on again.
This never used to happen. It has plenty of memory. Settings tells me that I have over 88 gbts left. (I bought a 130gbs one). It's a few years old now but I can't recall exactly when I bought it. Would be grateful if anyone has any ideas as to what the problem can be.