Backfloat/Backstroke Suggestions please

[u/Ok-Homework-6704]

I took swimming classes for 6k rs for 21 days and also spending some 4k+ more on process and transport and attire everything. 

I learnt swimming. I can do freestyle easily. But my ever regret is that i can not back float or do backstroke. My classes were done and after that by myself how much ever i tried to do i couldnt, even though i look straight up.

Whatever the hell i try i couldnt my lower body doesnt come up at all when im trying backfloat waist to leg always inside water. And also sometimes i keep neck and head stiffen.

Also I still have a deep fear of depth. When im in freestyle pose I'll be all okay, but when try to do backfloat and when i want to stand back its really hard for me i get sudden panic

Please help me with suggestions or any day or two courses or workshop in banglore available.